Lewis & Short

jējūno, 1, v. n. [com. ], to fast (late Lat.): Abraham peregrinis prandentibus cibos jejunaturus apposuit, Hier. Ep. 66, 11: cum jejunas laeta sit facies tibi, id. ib. 22, 27.

        1. (β) With dat., to abstain from a thing: Adam salvus alioquin, si uni arbusculae jejunare maluisset, Tert. Jejun. 3.
          With ab: a justa fruge naturae, Tert. Pud. 16.
          Trop.: philosophiā, Tert. Anim. 6.