Main Entry: ir·re·vers·ible

Pronunciation: \ˌir-i-ˈvər-sə-bəl\

Function: adjective

: incapable of being reversed : not reversible <an irreversible medical procedure>: as a : impossible to make run or take place backward <irreversible chemical syntheses> b of a colloid : incapable of undergoing transformation from sol to gel or vice versa c of a pathological process : of such severity that recovery is impossible <irreversible brain damage>

—ir·re·vers·ibil·i·ty \-ˌvər-sə-ˈbil-ət-ē\ noun, plural ir·re·vers·ibil·i·ties

—ir·re·vers·ibly \-ˈvər-sə-blē\ adverb