seethe / sē[voicedth]/ • v. [intr.] (of a liquid) bubble up as a result of being boiled: the brew foamed and seethed. ∎ [tr.] archaic cook (food) by boiling it in a liquid: others were cut into joints and seethed in cauldrons made of the animal's own skins. ∎ (of a river or the sea) foam as if it were boiling; be turbulent: the gray ocean seethed. ∎ [intr.] (of a person) be filled with intense but unexpressed anger: inwardly he was seething at the slight to his authority. ∎ (of a place) be crowded with people or things moving about in a rapid or hectic way: the entire cellar was seething with spiders the village seethed with life. ∎ (of a crowd of people) move in a rapid or hectic way: we cascaded down the stairs and seethed across the station | [as adj.] (seething) the seething mass of commuters.