the.com/shellac

means A resin secreted by the lac insect, dissolved in alcohol to make a glossy wood finish or varnish — and, by extension, slang for a total defeat ('getting shellacked').

from From 'shell' + 'lac,' with 'lac' tracing back through French and Hindi to the Sanskrit word for 'hundred thousand' (lakh) — a nod to the countless tiny lac insects whose resinous secretions are scraped from tree branches to make it. Flattened into thin sheets, the raw resin looked like little shells, hence the English name. The verb 'to shellac,' meaning to thrash or defeat someone, emerged later — possibly from the idea of giving someone a hard, glossy 'coating,' or simply from drinkers using the varnish's potent solvent as slang for getting completely wasted, which slid into meaning utterly beaten.