1580s, "advance, proceed," from go (v.) + on (adv.). Meaning "behave, carry on" is from 1777; especially "to talk volubly" (1863). As an expression of derision by 1886.

1909, "with one side facing," from side (n.) + on (adv.), perhaps based on earlier head-on. In reference to a vehicle collision, by 1828.

"capable of being approached, attainable," 1680s, from come + at + -able.

representing the common pronunciation of the verbal phrase come on, by 1929. Come on! as an urge to advance or go with is from mid-15c. (see come).

1640s, "come as something additional," from Latin supervenire "come on top of, come in addition to, come after, follow upon," from super "over, upon" (see super-) + venire "to come," from a suffixed form of PIE root *gwa- "to go, come." Related: Supervened; supervening.

Old English strange "strongly, violently, severely, furiously" (alongside strongly), from the same source as strong (adj.). Going strong (1898) is from racing. To come on strong was originally come it strong (1812).

"future events; time to come," late 14c., modeled on Latin futura, neuter plural of futurus (see future (adj.)).

1570s, "to come between in space or time" (obsolete); c. 1600, "to interpose on behalf of another," a back-formation from intercession, or else from Latin intercedere "intervene, come between, be between" (in Medieval Latin "to interpose on someone's behalf"), from inter "between" (see inter-) + cedere "to go" (from PIE root *ked- "to go, yield"). Related: Interceded; interceding.

1834, from bathos on the model of pathetic (q.v.), which, however, does not come directly from pathos, so the formation is either erroneous or humorous. Bathotic (1863, perhaps on model of chaotic) is not much better.

"approaching, nearing," 1834, from on + coming, present participle of come (v.). Oncome (n.) "initial stages, onset" (of an effort, rain, snow, a disease, etc.) is from late 12c.