c. 1300, "breadth" (obsolete), from broad (adj.). Sense of "shallow, reedy lake formed by the expansion of a river over a flat surface" is a Norfolk dialect word from 1650s. Meaning "the broad part" of anything is by 1741.
Slang sense of "woman" is by 1911, perhaps suggestive of broad hips, but it also might trace to American English abroadwife, word for a woman (often a slave) away from her husband. Earliest use of the slang word suggests immorality or coarse, low-class women. Because of this negative association, and the rise of women's athletics, the track and field broad jump (1863) was changed to the long jump c. 1967.
"ponder, turn over in one's mind," 1873, perhaps from a figurative use of mull (v.) "grind to powder" (which survived into 19c. in dialect), from Middle English mullyn, mollen "grind to powder, soften by pulverizing," also "to fondle or pet" (late 14c.), from Old French moillier and directly from Medieval Latin molliare,mulliare, from Latin molere "to grind," from PIE root *mele- "to crush, grind."
Of uncertain connection to the mull (v.) defined in Webster's (1879) as "to work steadily without accomplishing much," and the earlier identical word in athletics meaning "to botch, muff" (1862). Related: Mulled; mulling.
1784, "one who has a taste for some art, study, or pursuit, but does not practice it," from French amateur "one who loves, lover" (16c., restored from Old French ameour), from Latin amatorem (nominative amator) "lover, friend," agent noun from amatus, past participle of amare "to love" (see Amy).
The meaning "one who cultivates and participates (in something) but does not pursue it professionally or with an eye to gain" (as opposed to professional) is from 1786; often with disparaging suggestions of "dabbler, dilettante," but not in athletics, where the disparagement shaded the professional, at least formerly. As an adjective, by 1838.
1610s, " to enter or be put in rivalry with," from French compéter "be in rivalry with" (14c.), or directly from Late Latin competere "strive in common, strive after something in company with or together," in classical Latin "to meet or come together; agree or coincide; to be qualified," from com "with, together" (see com-) + petere "to strive, seek, fall upon, rush at, attack" (from PIE root *pet- "to rush, to fly").
According to OED, rare 17c., revived from late 18c. in sense "to strive (alongside another) for the attainment of something" and regarded early 19c. in Britain as a Scottish or American word. Market sense is from 1840s (perhaps a back-formation from competition); athletics sense attested by 1857. Intransitive use is by 1974. Related: Competed; competing.
Old English meaning "ligaments, tendons" is preserved in hamstring (n.), heart-strings. Meaning "limitations, stipulations" (1888) is American English, probably from the common April Fool's joke of leaving a purse that appears to be full of money on the sidewalk, then tugging it away with an attached string when someone stoops to pick it up.
To pull strings "control the course of affairs" (1860) is from the notion of puppet theater. First string, second string, etc. in athletics (1863) is from archers' custom of carrying spare bowstrings in the event that one breaks. Strings "stringed instruments" is attested from mid-14c. String bean is from 1759; string bikini is from 1974.
Track record (1955) is a figurative use from racing, "performance history" of an individual car, runner, horse, etc. (1907, but the phrase was more common in sense "fastest speed recorded at a particular track"). To make tracks "move quickly" is American English colloquial first recorded 1835; to cover (one's) tracks in the figurative sense first attested 1898; to keep track of something is attested from 1883. American English wrong side of the tracks "bad part of town" is by 1901. Track lighting attested from 1970.