"style of speech," early 15c., from Latin locutionem (nominative locutio) "a speaking, speech, discourse; way of speaking," noun of action from past participle stem of loqui "to speak," from PIE root *tolkw- "to speak." Related: Locutionary.
locomotor
loco-weed
locum-tenens
locus
locust
locution
locutory
lode
loden
lodestar
lodestone