applaud (v.)

late 15c. (implied in applauding), "to express agreement or approval; to praise," from Latin applaudere "to clap the hands in approbation, to approve by clapping hands; to strike upon, beat," from assimilated form of ad "to" (see ad-) + plaudere "to clap" (see plaudit). The sense of "clap the hands" is from 1590s; the extended meaning arrived in English before literal. Related: Applauded.