mode (n.2) Look up mode at Dictionary.com
"current fashion," 1640s, from French mode "manner, fashion, style" (15c.), from Latin modus "manner" (see mode (n.1)).
mode (n.1) Look up mode at Dictionary.com
"manner," late 14c., "kind of musical scale," from Latin modus "measure, extent, quantity; proper measure, rhythm, song; a way, manner, fashion, style" (in Late Latin also "mood" in grammar and logic), from PIE root *med- "to measure, limit, consider, advise, take appropriate measures" (see medical (adj.)). Meaning "manner in which a thing is done" first recorded 1660s.