WordNet sense 1 (something curved in shape):

arc

WordNet sense 2 (bending the head or body or knee as a sign of reverence or submission or shame):

obeisance, bowing

WordNet sense 3 (an appearance by actors or performers at the end of the concert or play in order to acknowledge the applause of the audience):

curtain call

WordNet sense 4 (a knot with two loops and loose ends; used to tie shoelaces):

bowknot

WordNet sense 5 (front part of a vessel or aircraft):

fore, prow, stem

WordNet sense 6 (bend one's back forward from the waist on down):

bend, crouch, stoop

WordNet sense 7 (bend one's knee or body, or lower one's head):

bow down

WordNet sense 8 (submit or yield to another's wish or opinion):

accede, defer, submit, give in