batch (n.)

late 15c., probably from a survival of an unrecorded Old English *bæcce "something baked" (compare Old English gebæc) from bacan "bake" (see bake (v.)). Generalized sense of "an aggregation of similar articles" is from 1590s. Batch is to bake as watch (n.) is to wake and match (n.2) "one of a pair" is to make. Extended 1713 to "any quantity produced at one operation."

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Definitions of batch from WordNet
batch (n.)
all the loaves of bread baked at the same time;
batch (n.)
(often followed by `of') a large number or amount or extent;
a batch of letters
Synonyms: deal / flock / good deal / great deal / hatful / heap / lot / mass / mess / mickle / mint / mountain / muckle / passel / peck / pile / plenty / pot / quite a little / raft / sight / slew / spate / stack / tidy sum / wad
batch (n.)
a collection of things or persons to be handled together;
Synonyms: clutch
batch (v.)
batch together; assemble or process as a batch;