Controlled vocabulary
An authorized term list that maps every variant onto one preferred label, so the same thing is not 'folder' here and 'directory' there.
See it
What it is
A controlled vocabulary is an authorized set of terms that maps every variant people actually type onto a preferred label. The product version is the simple end of that: 'Workspace' (not team, org, account), 'Sign in' (not log in, login, log-in). The idea comes from library science, where thesauri like MeSH and Library of Congress Subject Headings do considerably more, holding preferred terms, entry terms that point at them, and hierarchical or associative relationships between concepts. Product teams borrowed the small version for UI strings, docs, and support macros.
Reach for one the moment more than one person writes copy, or the moment an AI starts generating it. Naming drift is invisible per screen and obvious across a flow: the nav says 'Projects', the empty state says 'boards', the billing page says 'workspaces', and the user quietly assumes those are three features. A vocabulary is also the cheapest thing to hand a model: paste the approved list into the prompt and half the inconsistency disappears.
Gotcha: a controlled vocabulary is not a glossary. A glossary defines terms, a controlled vocabulary decides between them, so every row needs the rejected variants written next to the winner or nobody can tell what changed. Second gotcha: do not delete the folk words. Keep them as 'use for' pointers so site search, help center search, and your own SEO still catch the people typing 'login'.
Ask AI for it
Build a controlled vocabulary for this product. Scan the UI strings, docs, and marketing copy provided, find every concept that is named more than one way, and output a table with four columns: approved term, part of speech and casing, rejected variants ('use for' terms kept for search), and a one-line rule for when the term applies. Pick the winner by what users actually say, not by what sounds most formal. Cap it at 30 rows, flag any pair where the choice is genuinely contested, and end with a find-and-replace list of variant to approved term.