The quality of technical documentation is decided at the level of individual terms. The moment you start building a glossary for an equipment manual, you face a judgment problem before a methodology problem: out of hundreds of collected term candidates, which ones do you register as standard terms, which do you deliberately leave unmanaged, and when candidates conflict, which one wins?
These decisions matter more in some product categories than others. In consumer products — fans, refrigerators, phones — a slightly inconsistent term rarely affects user safety. Industrial equipment, construction machinery, robotics, and medical devices are different. Documentation in these B2B categories tends to be less standardized to begin with, yet a single wrong or ambiguous term can lead directly to operator injury or equipment damage. These are also the products whose manuals are most often localized into ten, twenty, or more languages — which means every weakness in the English source glossary is multiplied across every target language during manual localization.
This guide gives you decision criteria you can apply directly at the “standard term decision” stage of terminology management. The overall six-step terminology workflow is covered in our blog article “Translation quality is decided at the term level”; this guide expands that single stage into a working reference for technical writing and manual development teams.
Which Terms Belong in a Technical Documentation Glossary
If a term meets any one of the criteria below, review it as a candidate for standardization.
- Official names. Names used in engineering drawings, specifications, the BOM, and the UI: equipment part names, major component names, function names, UI menu and button labels.
- Inconsistent terms. The same object referred to by different names within a document or across documents. Confirmed inconsistencies are the highest-priority standardization targets.
- Proper nouns and designated terms. Product names, technology names, and company names — brand proper nouns and terms designated by the client or product owner.
- High-frequency action verbs. Terms repeated across documents and procedures — especially the core action verbs of installation, operation, and maintenance. Verbs deserve standardization too: pick one of “remove / detach / take off” and control the rest.
- Safety signal words and label text. Signal words and wording used on safety warning labels.
- Prohibited terms and DNT items. Blocked expressions and do-not-translate (DNT) terms.
- Variant forms. Abbreviation versus full form (“MCV” vs. “Main Control Valve”), US versus UK spelling, and hyphenation or capitalization variants that need a single controlled form.
- Safety-critical terms. Terms where mistranslation or confusion can lead to injury or equipment damage: gas, chemicals, interlocks, grounding, high-voltage, and chamber-related terminology.
- Terms defined in regulations and standards. Terms with regulatory or standards-based definitions, such as ANSI Z535 signal words, EMO (Emergency Off), Hazardous Energy Isolation, and Exhaust Ventilation.
Which Terms to Leave Out of the Glossary
Fewer standard terms are better. When the count grows unchecked, the accuracy of application, review, and maintenance all drop together — and a glossary that is merely large ends up being a glossary nobody consults. If a term matches the descriptions below, you do not need to register it.
- Generic nouns with no special meaning constraints — widely used part names such as common bolts and nuts, or the names of ordinary repair tools and measuring instruments.
- Terms with low document frequency and low likelihood of reuse.
- Terms with no history of confusion and little future risk of it — words like power, standby, and restart that have been used stably with the same meaning across the product line.
- Terms where variation creates no risk or confusion for the user.
How to Decide the Standard Term
Once the standardization targets are set, decide which expression becomes the standard term. Apply the principles below.
- Operator comprehension first. Choose expressions the operator or technician will understand clearly over expressions that only make sense inside the engineering organization. If a drawing or BOM term will not work for the end user, coin a new standard term.
- Match physical labels and the UI. Terms printed on the equipment or shown in the UI must be matched exactly in the documentation, even when the wording is awkward. When the screen and the manual disagree, the user pays for it.
- Keep regulatory and standards definitions. If a term is defined in an applicable industry standard or regulation, keep the defined form.
- Specificity and distinctiveness. The standard term must be specific in meaning and impossible to confuse with other parts or functions.
- Translation stability. Choose source expressions whose meaning survives translation. An ambiguous English source term will be interpreted differently in every target language — the source glossary is the pivot for the entire multilingual set, so control ambiguity at the source. Controlled-language practices such as “one word, one meaning” apply directly here.
- Respect established usage. A term already entrenched in the industry and in the field should generally be kept, even if slightly imprecise, as long as it creates no real risk of error. Replacing an established term in the name of precision usually creates more confusion than it removes.
- Case in practice ① Standard-term decisions — candidate comparison and rationale
- One name, one concept (specificity and distinctiveness). In an industrial-equipment standardization project, charging-related terms were tangled across the source: a single expression was being used for two different parts. We split the concepts — the fixed port on the equipment became “charging inlet” and the cable-side component became “charging connector” — and defined each as a separate standard term. Two definition lines resolved what had been a running source-text ambiguity.
- Consolidating drift (inconsistent terms). The same driveline component appeared as “drive axle,” “drive shaft,” and “axle” depending on the document. All three were collected as candidates, one representative term was fixed as the standard, and the others were registered as prohibited variants.
- Client-designated term takes priority. “Hydraulic oil” and “hydraulic fluid” were mixed throughout the source. The client’s internal corporate standard designated one form, so it was fixed as the standard term and the other registered as prohibited.
- Established terminology versus shop slang. Field crews commonly say “diff,” but shop slang is not established terminology. The standard term “differential” was kept. The “respect established usage” principle applies to expressions fit for documentation — it does not promote spoken slang into the glossary.
Resolving Term Conflicts: A Priority Order
When candidate expressions conflict, apply the order below. A higher criterion overrides a lower one.
- Terms mandated by law, regulation, or applicable standards
- Terms contractually designated by the client or product owner
- Wording physically present on equipment labels and in the UI
- Corporate standard terminology
- Industry-convention terminology
Glossary Entry Format
- One concept, one term. Register exactly one term per concept. If synonyms must be recorded, register every non-standard expression explicitly as a prohibited variant.
- Definitions are mandatory. Every standard term gets a definition. A term without a definition is a judgment call only its author can repeat.
- Data fields. At the start, a spreadsheet is enough. Manage these as the base fields: standard term, definition, prohibited variants, source, registration date, and change history.
Alongside the glossary itself, establish a governance system: who decides term registration, change, and retirement, and by what procedure. A glossary without governance eventually becomes a source of new inconsistency in its own right.
- Case in practice ② Sample glossary entries — standard term, definition, prohibited variants
- Piston Seal Definition — Sealing component fitted on the piston circumference of a hydraulic cylinder to prevent fluid leakage.
Prohibited variants — piston packing, piston cup, piston sealing - Manual Service Disconnect (MSD) Definition — Safety device used to manually break the high-voltage circuit before service work.
Prohibited variants — service plug, HV safety plug, high-voltage plug - Ground Terminal Definition — Terminal connecting an electrical circuit to the chassis ground.
Prohibited variants — earth terminal, earth tab
All three entries come from a real industrial-equipment manual standardization project — the four piston-seal variants, for instance, were all found within a single service manual before consolidation. For safety-critical high-voltage terms like the Manual Service Disconnect, registering the prohibited variants is as important as fixing the standard term: a single stray variant left in the source can make a technician mistake one component for another, in the English manual and in every localized manual downstream. The Ground Terminal entry shows the same mechanism applied to regional variants: fixing the US form and prohibiting “earth terminal” keeps US and UK usage from mixing across the documentation set.
Finalizing the Multilingual Glossary Before Manual Localization Begins
Once the English source terminology is finalized, lock the multilingual glossary before body translation starts, in this order:
- Batch-translate the finalized standard terms into every target language.
- Have in-country subject-matter experts review the translated terms.
- Incorporate the reviews and finalize the multilingual glossary.
- Load the finalized glossary as a termbase into the CAT environment.
- During body translation in each language, ensure the designated terms are surfaced and enforced in real time.
The point where localization projects most often go wrong is a term change after body translation has started. Enter translation without a locked glossary and each language settles on its own rendering; unwinding that afterwards costs far more than finalizing the glossary up front — and the rework multiplies by the number of target languages. At twenty or thirty languages, a single unlocked term becomes twenty or thirty cleanup projects.
How Much Terminology Management Should Stay In-House?
The criteria for selecting and deciding terms can be summarized as above. The real difficulty is not the criteria themselves but applying them consistently at scale. As the documentation set grows to dozens of manuals and the target languages multiply, keeping one fixed standard term applied identically across every document and every language — and updating it at every revision — quickly becomes a significant burden on technical writing teams.
Safety-critical terminology raises the stakes further: a single point of inconsistency can translate into an injury or equipment incident, so verification cost and risk grow together with scale. This is where a partner with dedicated terminologists, purpose-built tooling, and accumulated multilingual terminology assets earns its place in the manual development and localization workflow.
Terminology Management Checklist
☐ Were standardization targets selected against the nine selection criteria?
☐ Are any terms matching the exclusion criteria mixed into the managed set?
☐ Does every standard term have a written definition?
☐ Is any single concept carrying more than one registered standard term?
☐ Are prohibited variants registered alongside each standard term where variants exist?
☐ Do documentation terms match the physical wording on equipment labels and in the UI?
☐ Was the priority order applied to every conflicting term?
☐ Are the procedure and decision owner defined for term registration, change, and retirement?
☐ Was the multilingual glossary finalized and pre-loaded into translation memory and the termbase before multilingual rollout?