n. & adj.
n. 1 an aperture or gap, esp. allowing access. 2 a favourable situation or opportunity. 3 a beginning; an initial part. 4 Chess a recognized sequence of moves at the beginning of a game. 5 a counsel's preliminary statement of a case in a lawcourt.
adj. initial, first. opening-time Brit. the time at which public houses may legally open for custom.