a. the first in counterclockwise order of the bases from home plate.
b. the position of the player covering the area of the infield near first base.
2. get to first base, Informal.
a. to succeed in the initial phase of a plan or undertaking: His suggestions for labor-saving techniques never got to first base.
b. to engage in petting that goes no further than kissing.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.