"half-asleep," 1845, from Latin somnolentus "sleepy" (see somnolent) + -escent.
Entries linking to somnolescent
somnolent adj.
"sleepy, lethargic, drowsy, inclined to sleep," mid-15c., sompnolent, from Old French sompnolent, somnolent (Modern French somnolent) and directly from Latin somnolentus (in Medieval Latin also sompnolentus) "sleepy, drowsy," from somnus "sleep" (from PIE root *swep- "to sleep"). Respelled 17c. on Latin model; for the -p-, compare solemn.
-escent
word-forming element meaning "beginning, becoming, tending to be," from Latin -escentem (nominative -escens), ending of present participles of verbs in -escere.