Etymologies are usually staid affairs; whether they are long lists of preforms and cognates or simple statements that the origin is unknown, they are devoid of passion, humor, and exclamation marks. Not so that of the OED’s coil2 “Noisy disturbance, ‘row’; ‘tumult, turmoil, bustle, stir, hurry, confusion’”:
[First in 16th c.: of unknown origin. Prob. a word of colloquial or even slang character, which rose into literary use; many terms of similar meaning have had such an origin; cf. pother, row, rumpus, dirdum, shindy, hubbub, hurly-burly, etc.
The conjectures that coil may be ‘related’ to Gael. coileid ('koletʃ) ‘stir, movement, noise’, or to goilim ('golɪm) ‘I boil’, goileadh, ‘boiling’, or to goill (goλ) ‘shield, war, fight’, are mere random ‘shots’, without any justification, phonetic or historical. Coil is unknown in Scotland, and no evidence connects it with Ireland. Gaelic or Irish words do not enter English through the air, with phonetic change on the way!]
Somebody was feeling mighty frisky in the Scriptorium that day!
Incidentally, definition 4 b. is “mortal coil: the bustle or turmoil of this mortal life. A Shaksperian expression which has become a current phrase.” Note the quaint spelling “Shaksperian”; in the list of authors he’s Shakespeare as usual. Yup, mighty frisky.
Addendum. Now see this post translated into Latin at Sauvage Noble!