Residual

Part of speech: adjective

Pronunciation: /ɹɪˈzɪd͡ʒ.ʊəl/

Definitions

1. Something that remains after the main part has been removed or completed
2. A remainder that persists after the primary substance has been taken away or finished
3. An amount or quantity that continues to exist beyond the principal portion that has been eliminated or concluded

Etymology: The adjective "residual" sits at the end of a long chain of Latin verbs meaning "to sit." Its ancestor, Latin "resideō," literally meant "to sit back" or "to remain behind," built from "re-" (back, again) and "sedeō" (to sit), the same root that gives English "sedentary" and "session." From its past participle "residuus," meaning "remaining, left over," Latin formed the neuter noun "residuum," "a remainder," which passed into Old French as "residu" and then into English as "residue" during the Middle English period. The adjective came later. "Residual" was recorded in English from 1570, so it arrived as a formation from the noun, describing whatever stays behind once the rest has been taken away. That sense of leftover material is what has kept it useful in technical settings, from chemistry and mathematics to statistics, where a "residual" is the part of a quantity that remains after a calculation or removal.

Synonyms: remaining, leftover, surplus

Antonyms: total, complete