lysis (n.)

scientific/medical word-forming element meaning "loosening, dissolving, dissolution," from Greek lysis "a loosening, setting free, releasing; dissolution; means of letting loose," from lyein "to unfasten, loose, loosen, untie," from PIE root *leu- "to loosen, divide, cut apart."

Proto-Indo-European root meaning "to loosen, divide, cut apart."

It forms all or part of: absolute; absolution; absolve; analysis; analytic; catalysis; catalyst; catalytic; dialysis; dissolve; electrolysis; electrolyte; forlorn; Hippolytus; hydrolysis; -less; loess; loose; lorn; lose; loss; Lysander; lysergic; lysis; -lysis; lyso-; lysol; lytic; -lytic; palsy; paralysis; pyrolusite; resolute; resolution; resolve; soluble; solute; solution; solve; solvent.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit lunati "cuts, cuts off," lavitram "sickle;" Greek lyein "to loosen, untie, slacken," lysus "a loosening;" Latin luere "to loose, release, atone for, expiate;" Old Norse lauss "loose, free, unencumbered; vacant; dissolute;" Old English losian "be lost, perish."

1927, back-formation from lysis. Related: Lysed; lysing.