Lewis & Short

hālo, āvi, ātum, 1, v. n. and a., to breathe (poet.; cf.: feo, spiro).

  1. I. Neutr., to breathe, to emit vapor or fragrance, be fragrant: invitent croceis halantes floribus horti, Verg. G. 4, 109: ture calent arae sertisque recentibus halant, id. A. 1, 417.
  2. II. Act., to breathe out, exhale: et nardi florem, nectar qui naribus halat, Lucr. 2, 848; 6, 221; 391; Mart. 10, 48.