Meaning

noun a negatively charged electrode that is the source of electrons entering an electrical device

noun the positively charged terminal of a voltaic cell or storage battery that supplies current

originFrom Ancient Greek κατα- (kata-, “down”) and ὁδός (hodós, “journey, way”), equivalent to Ancient Greek κάθοδος (káthodos, “way down, descent”). Coined by English polymath William Whewell in 1834 for Michael Faraday, who introduced it later that year. By surface analysis, cath- (alternative form of cata-) + -ode.

Etymology from Wiktionary, CC BY-SA 3.0