Bore, with ‘down.’

noun

1. The rounded prominence formed by the ends of the two adjacent bones at a joint
2. The joint of a knuckle
3. A cut of meat consisting of the tarsal or carpal joint with the adjoining flesh
4. The meeting of two surfaces at a sharp angle (as in a roof)
5. A pivotal point
6. A set of metal finger rings or guards attached to a transverse piece and worn over the front of the doubled fist for use as a weapon

verb

1. To place the knuckles on the ground in shooting a marble
2. To press or rub with the knuckles

adjective or adverb

1. Not using boxing gloves

   "… champion bare-knuckle prizefighter of England …"

2. Having a fierce unrelenting character

   "bare-knuckle politics"

verb

1. To apply oneself earnestly

verb

1. Give in, submit

adjective

1. Marked by, causing, or experiencing tense nervousness

   "a white-knuckle ride on a roller coaster"