Easton's Bible Dictionary
The curb put into the mouths of horses to restrain them. The Hebrew word (metheg) so rendered in Psalm 32:9 is elsewhere translated "bridle" (2 Kings 19:28; Proverbs 26:3; Isaiah 37:29). Bits were generally made of bronze or iron, but sometimes also of gold or silver. In James 3:3 the Authorized Version translates the Greek word by "bits," but the Revised Version by "bridles."
Noah Webster's New International Dictionary of the English Language
1. (n.) The part of a bridle, usually of iron, which is inserted in the mouth of a horse, and having appendages to which the reins are fastened.
2. (v.) Fig.: Anything which curbs or restrains.
3. (v. t.) To put a bridle upon; to put the bit in the mouth of.
4. (v.) imp. & p. p. of Bite.
5. (n.) A part of anything, such as may be bitten off or taken into the mouth; a morsel; a bite. Hence: A small piece of anything; a little; a mite.
6. (v.) Somewhat; something, but not very great.
7. (n.) A tool for boring, of various forms and sizes, usually turned by means of a brace or bitstock. See Bitstock.
8. (n.) The part of a key which enters the lock and acts upon the bolt and tumblers.
9. (n.) The cutting iron of a plane.
10. (v.) In the Southern and Southwestern States, a small silver coin (as the real) formerly current; commonly, one worth about 12 1/2 cents; also, the sum of 12 1/2 cents.
11. (p. p.) 3d sing. pr. of Bid, for biddeth.
12. (imp.) of Bite
13. (p. p.) of Bite