vent feather (ventfera"er)

In ornith., one of the under tail-coverts; a cri al feather lying under the tail, behind the anus. See cri um, tectrices. vent-field (vent'feld), n. In ordnance , a raised plate or tablet through which the vent is bored. When the modern percu ion-lock is used, the vent-field serves to support it. vent-gage (vent'gāj), n. A wire of prescribed size for measuring the diameter of a vent.