GROIN
Groin, n. Etym: [F. groin, fr. grogner to grunt, L. grunnire.]

Defn: The snout of a swine. [Obs.] Chaucer.

GROIN
Groin, v. i. Etym: [F. grogner to grunt, grumble.]

Defn: To grunt to growl; to snarl; to murmur. [Obs.] Chaucer.
Bears that groined coatinually. Spenser.

GROIN Groin, n. Etym: [Icel. grein distinction, division, branch; akin to Sw. gren, branch, space between the legs, Icel. greina to distinguish, divide, Sw. grena to branch, straddle. Cf. Grain a branch.]

1. (Anat.)

Defn: The line between the lower part of the abdomen and the thigh, or the region of this line; the inguen.

2. (Arch.)

Defn: The projecting solid angle formed by the meeting of two vaults, growing more obtuse as it approaches the summit.

3. (Math.)