svelte adj.

word-forming element, in English meaning usually "out of, from," but also "upwards, completely, deprive of, without," and "former;" from Latin ex "out of, from within; from which time, since; according to; in regard to," from PIE *eghs "out" (source also of Gaulish ex-, Old Irish ess-, Old Church Slavonic izu, Russian iz). In some cases also from Greek cognate ex, ek. PIE *eghs had comparative form *eks-tero and superlative *eks-t(e)r-emo-. Often reduced to e- before -b-, -d-, -g-, consonantal -i-, -l-, -m-, -n-, -v- (as in elude, emerge, evaporate, etc.).

1640s, "to shake or disturb by violent, irregular action" (transitive); 1680s, "to draw or contract spasmodically or involuntarily" (intransitive); from Latin convulsus, past participle of convellere (transitive only) "to pull away, to pull this way and that, wrench," hence "to weaken, overthrow, destroy," from assimilated form of com "with, together" (see con-) + vellere "to pluck, pull violently" (see svelte). Related: Convulsed (1630s); convulsing.