Meaning 1 ►▼
A player is out if he doesn't hit the ball hard enough to get to first base and is tagged out. If he gets to first base, he may score a run.
The batter hit a line drive and got to first base.
Meaning 2 ►▼
to advance something, to do well enough to get a good start on something
I wish I could get to first base with my boss.