Lewis Short
(adjective) : irrĭtus (inr-), a, um, 2. inratus
* Invalid.
* Lit.
* Undecided, unfixed, void, of no effect: quod modo erat ratum, irritum est,Ter. Phorm, 4, 7, 58: testamentum irritum facere,Cic. Phil. 2, 42, 109: testamentum pro irrito habere,Suet. Tib. 51; Gai. Inst. 2, 146 sq.; Paul. Sent. 3, 5, 14: injurias rescindere et irritas facere,Cic. Verr. 2, 2, 26, § 63: quaeque augur injusta, nefasta, vitiosa, dira, defixerit, inrita infectaque sunto,id. Leg. 2, 8, 21: omnia ab iis acta,Vell. 2, 43, 1: pacta,Sil. 6, 696: Tiberii voluntas,Suet. Calig. 14: somnia,of no significance,id. Aug. 91: Remus aves irritas habuit,Gell. 13, 14.
* Transf., of persons, that does or undertakes a thing in vain, to no purpose, without effect.
* With gen.: irritus legationis,Tac. H. 4, 32: consilii,Vell. 2, 63, 2: propositi,Val. Max. 4, 3, 3 ext.: spei,vainly hoping,Curt. 6, 5, 31: incepti,Sil. 7, 131.
* Absol.: variis assultibus irritus urget,Verg. A. 5, 442: venit et e templis irrita turba domum,without a response,Tib. 2, 3, 22: irriti legati remittuntur,Tac. A. 15, 25: domum irritus rediit,Sen. Ben. 6, 11: discedere irritum putebat,Curt. 4, 4, 2: irritus qui habebatur, laudabatur, good for nothing, Cat. ap. Gell. 11, 2, 2.—Subst.: irrĭtum, i, n., nothingness, vanity, worthlessness: spes ad irritum redacta,Liv. 28, 31: spes ad irritum cadens,id. 2, 6: victoria ad inritum revolvebatur,Tac. H. 3, 26: cecidisse in inritum labores,id. ib. 3, 53 fin.: irrita dicere,useless words,Ov. M. 11, 40.—Adv.: irrĭtē, in vain, Cassiod. Var. 1, 4; 12, 2.
Charlton T. Lewis, Charles Short, A Latin Dictionary