The product has a working vocabulary and an internal one. This page is the mapping, so that if you meet an internal word — in an older thread, a support reply, or an API field — you know what it means.
Retired terms
Words that are easy to confuse
These are not renames. Both words are correct; they mean different things.
interface · surface · doc · page
Interface is what the work is returned as (a sheet, a deck, a board). Surface is the category of interface. Doc is a stored, versioned file. Page is a screen in the app.
directory · workspace · organisation
Directory is the entity — one organisation or client. Workspace is only the sidebar group that holds Projects, Members and Teams.
variant · alternative · choice
Choice variable is the dimension being varied (price, timing). Variant is one built result. Alternative is an option the audit recorded as ruled out.
driver · metric
Driver is the measure a project is a bet on. Metric is also a milestone kind — a milestone that tracks a number rather than a deliverable.
task · run
Task is what you asked for. Run is one execution of it — re-running a task produces a second run.