"irritable, short-tempered," 1906, from snark (v.) "to find fault with, nag" (1882), literally "to snort" (1866), from an imitative source akin to Low German snarken, North Frisian snarke, Swedish snarka; and compare snarl, v.2, sneer, v.. Back-formation snark (n.) "caustic, opinionated, and critical rhetoric" is from c.2002 (compare snark, n.). Related: Snarkily; snarkiness.