2. prō-sĕro, sĕrŭi, sertum, 3, v. a., to stretch forth, extend (post-class.): aggeribus caput Alpinis proserit in Celtas (Rhodanus), Sil. 3, 447: proserit hydra caput, Avien. Arat. 1111: se, id. Perieg. 711, 342.