talking in one's sleep, 1847, from somni- "sleep" + -loquy, from Latin loqui "to speak" (from PIE root *tolkw- "to speak"). Related: Somniloquence (1814); somniloquent (1804, Coleridge); somniloquist; somniloquous; somniloquize.
somnambulate
somnambulation
somnambulism
somni-
somniferous
somniloquy
somnolence
somnolent
Somnus
son
son of a bitch