lead-off n.

"to guide," Old English lædan (transitive) "cause to go with oneself; march at the head of, go before as a guide, accompany and show the way; carry on; sprout forth, bring forth; pass (one's life)," causative of liðan "to travel," from Proto-Germanic *laidjanan (source also of Old Saxon lithan, Old Norse liða "to go," Old High German ga-lidan "to travel," Gothic ga-leiþan "to go"), from PIE *leit- (2) "to go forth."

Of roads, c. 1200. Meaning "to be in first place" is from late 14c. Intransitive sense, "act the part of a leader," is from 1570s. Sense in card playing, "to commence a round or trick," is from 1670s. Meaning "take the directing part in a musical performance or prayer" is from 1849. Related: Led; leading.

To lead with one's chin "leave oneself vulnerable in a contest" (1946) is a figure from boxing. To lead on "entice to advance" is from 1590s. To figuratively lead (someone) by the nose "guide by persuasion" is from 1580s, from draught animals (earlier lead by the sleeve, early 15c.). To lead (someone) a dance "compel through a course of irksome actions" is from 1520s.

by c. 1200 as an emphatic form of Old English of (see of), employed in the adverbial use of that word. The prepositional meaning "away from" and the adjectival sense of "farther" were not firmly fixed in this variant until 17c., but once they were they left the original of with the transferred and weakened senses of the word. Meaning "not working" is from 1861.

Off the cuff "extemporaneously, without preparation" (1938) is from the notion of speaking from notes written in haste on one's shirt cuffs. In reference to clothing, off the rack (adj.) "not tailored, not made to individual requirements, ready-made" is by 1963, on the notion of buying it from the rack of a clothing store; off the record "not to be publicly disclosed" is from 1933; off the wall "crazy" is 1968, probably from the notion of a lunatic "bouncing off the walls" or else in reference to carom shots in squash, handball, etc.