"to tangle, to catch in a snare or noose" (trans.), late 14c., from a noun snarl "a snare, a noose" (late 14c.), probably a diminutive of snare (n.1). Intransitive sense "become twisted or entangled" is from c. 1600. Related: Snarled; snarling.
"growl and bare the teeth," 1580s, perhaps from Dutch or Low German snarren "to rattle," probably of imitative origin (compare German schnarren "to rattle," schnurren "to hum, buzz"). Meaning "speak in a harsh manner" first recorded 1690s. Related: Snarled; snarling.
late 14c., "a snare, noose," from snarl (v.1). Meaning "a tangle, a knot" is first attested c. 1600. Meaning "a traffic jam" is from 1933.