second base is a noun meaning "the base that must be touched second by a base runner in baseball". It carries 2 recorded senses.
the base that must be touched second by a base runner in baseball
the fielding position of the player on a baseball team who is stationed near the second of the bases in the infield
Definitions, synonyms and semantic relations for second base come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.