Meaning

noun the basic unit of length adopted under the Systeme International d'Unites (approximately 1.094 yards)

noun any of various measuring instruments for measuring a quantity

noun (prosody) the accent in a metrical foot of verse

originFrom Middle English metere (“one who measures, measurer”), perhaps (with change in suffix) from Old English metend (“one who measures or metes”), equivalent to mete (“to measure”) + -er. The transference from "person who measures" to "device that measures" was probably assisted by association with -meter, as in barometer, etc. Cognate with Scots mettar, metter (“meter, measurer”), Saterland…

Etymology from Wiktionary, CC BY-SA 3.0