See under .
the property satisfied by a topological space in which the neighborhood system of each point has a base consisting of a countable number of neighborhoods (first axiom of countability) or the property satisfied by a topological space that has a base for its topology consisting of a countable number of subsets of the space (second axiom of countability)
noun 1. Baseball. Idioms 2. get to first base, Informal. noun 1. (baseball) 2. (informal, mainly US & Canadian) get to first base, to accomplish the first step of an undertaking noun phrase In early sexual play, holding hands: ”In sixth grade,” she said, ”first base is holding hands, and second base is kissing on […]
noun, Baseball. 1. the player whose position is first base.
- First blood
noun 1. the first killing or wounding in a fight or war 2. the first damage or reverse inflicted on an opponent in a conflict
- First blush
noun first glance or sight, initial occurrence Usage Note used in “at first blush” see: at first blush