method of exercise and a fad in early 1980s, American English, coined 1968 by U.S. physician Kenneth H. Cooper (b. 1931), from aerobic (also see -ics) on the notion of activities which require modest oxygen intake and thus can be maintained.

method of painting, 1868, from French gouache "watercolors, water-color painting" (18c.), from Italian guazzo "watercolor," originally "spray, splash, puddle, pool," from Latin aquatio "watering, watering place," from aquatus, past participle of aquari "to bring water for drinking," from aqua "water" (from PIE root *akwa- "water").

1838, literally "of the same measure," from iso- "the same, equal" + -metric. The components are Greek: isos "equal, identical" + metron "a measure." Originally a method of using perspective in drawing; later in reference to crystals. The physiological sense relating to muscular action is from 1889, from German isometrisch in this sense (1882).

1865, originally a device for making fire by the twirled stick method, from fire (n.) + drill (n.1). Meaning "rehearsal of what to do in a fire" is from 1884 (originally it also involved fighting the fire), from drill (n.) in the "agreed-upon procedure" sense (see drill (v.)).

1810 as a method of signalling, from homo- (1) "same" + -graph "something written." Meaning "a word of identical spelling with another, but of different origin and meaning," is from 1873. Related: Homographic; homography. Greek homographos meant "of the same letters."

late 14c., diafragma, in anatomy, "muscular membrane which separates the thorax from the abdominal cavity in mammals," from Late Latin diaphragma, from Greek diaphragma "partition, barrier, muscle which divides the thorax from the abdomen," from diaphrassein "to barricade," from dia "across" (see dia-) + phrassein "to fence or hedge in," which is of uncertain etymology. Beekes suggests it is a substrate word and finds "no convincing correspondence outside Greek."

The native word in the anatomical sense is midriff. From 1650s as "a partition" of any kind, "something which divides or separates;" 1660s in the special sense "thin piece of metal" serving some purpose (as a sound resonator, etc.). Meaning "contraceptive cap" is from 1933. Related: Diaphragmal; diaphragmatic.

method of betting in which the bettor must pick the first- and second-place finishers in correct order, 1971, from American Spanish perfecta, shortened from quiniela perfecta "perfect quiniela," a bet in horseracing (see quinella); for perfecta, see perfect (adj.).

word-forming element, principally in the science, forming names of disciplines describing natural laws or scientific methods; from Greek -nomia "method," -nomos "managing," nomos "law, usage, custom," all from the verb nemein "to manage," from PIE root *nem- "assign, allot; take." 

c. 1400, "act, process, or method of arithmetical calculation," from Latin computationem (nominative computatio), noun of action from past participle stem of computare "to sum up, reckon, compute," from com "with, together" (see com-) + putare "to reckon," originally "to prune," from PIE root *pau- (2) "to cut, strike, stamp." From 1713 as "a result of computation, amount reckoned."

1550s, method of divination said to have been practiced by a person walking in a circle marked with characters or signs till he fell from dizziness, the inference being drawn from the place in the circle at which he fell; from Medieval Latin gyromantia, from Greek gyyros "circle" (see gyro- (n.)) + manteia "divination, oracle" (see -mancy).