bow 2 
(bou)
(bou)v. bowed, bow·ing, bows
v.intr.
1. To bend or curve downward; stoop.
2. To incline the body or head or bend the knee in greeting, consent, courtesy, acknowledgment, submission, or veneration.
3. To yield in defeat or out of courtesy; submit. See Synonyms at yield.
v.tr.
1. To bend (the head, knee, or body) to express greeting, consent, courtesy, acknowledgment, submission, or veneration.
2. To convey (greeting, for example) by bending the body.
3. To escort deferentially: bowed us into the restaurant.
4. To cause to acquiesce; submit.
5. To overburden: Grief bowed them down.
n.
Phrasal Verb: An inclination of the head or body, as in greeting, consent, courtesy, acknowledgment, submission, or veneration.
bow out
Idiom: To remove oneself; withdraw.
bow and scrape
To behave obsequiously.
[Middle English bowen, from Old English būgan; see bheug- in the Appendix of Indo-European roots.]