Lewis Short
ob-sŏpĭo, īvi, or ĭi, ītum, 4
* V. a., to put or lull to sleep (post-class.): a somni tempore prohibere, ne obsopiantur,Scrib. Comp. 180: somno obsopitus,fallen asleep,Sol. 12: odoris novitate obsopitus,made faint, stupefied,id. ib.
Charlton T. Lewis, Charles Short, A Latin Dictionary