1580s, "second person of the Christian Trinity," from Gk. logos "word, speech, discourse," also "reason," from PIE base *leg- "to collect" (with derivatives meaning "to speak," on notion of "to pick out words;" see lecture
); used by Neo-Platonists in various metaphysical
and theological senses and picked up by N.T. writers. Other Eng. formations from logos include logolatry "worship of words, unreasonable regard for words or verbal truth" (1810 in Coleridge); logomachy "fighting about words" (1560s); logomania (1870); logophobia (1923).