ENGLISH
REFERENCE

operation

n. C / U
B1 Intermediate Oxford US //ˌɑpɝˈeɪʃən// UK //ˌɒpəɹˈeɪʃən// op·er·a·tion Archaic General-service

n. a planned action or a set of tasks to achieve a specific goal. It can also mean a medical surgery or the way a business or machine works.

n. a planned activity involving many people or parts; the state of being functional or in use. Also refers to a surgical procedure or a mathematical process.


SIMPLE

The rescue operation saved three people from the mountain.

CONTEXTUAL

The hospital staff prepared the room for a minor operation scheduled for early tomorrow morning.

COMPLEX

The logistics company streamlined its entire operation by implementing a new tracking system that monitors every delivery vehicle in real time.

Synonyms
Origin

Etymology tree Proto-Indo-European *h₃ep- Proto-Indo-European *-os Proto-Indo-European *h₃épos Proto-Italic *opos Latin opus Latin opera Proto-Indo-European *-h₂ Proto-Indo-European *-éh₂ Proto-Indo-European *-tós Proto-Indo-European *-eh₂tos Proto-Italic *-ātos Latin -ātus Latin operātus Latin operor Proto-Indo-European *-tisder. Proto-Italic *-tjō Latin -tiō Latin operātiōder. Old French operacionbor. Middle English operacioun English operation From Middle English operacioun, from Old French operacion, from Latin operātiō, from the verb operor (“to work”), from opus, operis (“work”). Equivalent to operate + -ion.

Usage

Uncountable when referring to the state of being active ('in operation'); countable when referring to specific instances like surgeries or business units.

Idioms1 entry

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