bear down

Short definition from Wiktionary

Verb

1. 1
   Used other than figuratively or idiomatically: see bear, down.
2. 2
   To steer away from the wind; to approach from windward.
3. 3
   To push (someone) to the ground; to defeat, overcome.
4. 4
   To maintain one's position against (someone) in a debate; to stand one's ground against.
5. 5
   To intensify one's efforts.
6. 6
   To approach in a determined manner.
7. 7
   To exert downward pressure on one's abdomen, as in giving birth, forcing out feces, and some similar bodily maneuvers.