1590s, "unable to pay one's debts," from in- (1) "not" + Latin solventem "paying" (see solvent). Originally of one who was not a trader; only traders could become bankrupt.
Entries linking to insolvent
in- 1
word-forming element meaning "not, opposite of, without" (also im-, il-, ir- by assimilation of -n- with following consonant, a tendency which began in later Latin), from Latin in- "not," cognate with Greek an-, Old English un-, all from PIE root *ne- "not."
In Old French and Middle English often en-, but most of these forms have not survived in Modern English, and the few that do (enemy, for instance) no longer are felt as negative. The rule of thumb in English has been to use in- with obviously Latin elements, un- with native or nativized ones.
solvent adj.
1650s, "able to pay all one owes," from French solvent, from Latin solventem (nominative solvens), present participle of solvere "to loosen, release, accomplish, fulfill," from PIE *se-lu-, from reflexive pronoun *s(w)e- (see idiom) + root *leu- "to loosen, divide, cut apart." The chemical meaning "having the power of dissolving" is by 1680s.
insolvency n.
1660s, from insolvent (q.v.) + abstract noun suffix -cy. Insolvence (1793) is rare.