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grātor, ātus, 1, v. dep. n. and a. [gratus], to manifest joy, to wish one joy, to congratulate, to rejoice with, rejoice (mostly poet. or in post-Aug. prose; not in Cic.; class. gratulor, congratulor): nec tibi me in hac re gratari decet, Att. ap. Serv. Verg. A. 5, 40: inveni, germana, viam: gratare sorori, Verg. A. 4, 478; Ov. M. 6, 434: invicem inter se gratantes, Liv. 9, 43, 17: nescia, gratentur consolenturne parentem (by zeugma), Ov. M. 1, 578: Jovis templum gratantes ovantesque adire, Liv. 7, 13, 10: laudantes gratantesque, Tac. H. 2, 29: inter venerantes gratantesque, id. A. 2, 75: ad gratandum sese expedire, id. ib. 14, 8; Ov. F. 3, 418.
With acc.: gratatur reduces (= eos reduces esse), congratulates them on their return, Verg. A. 5, 40; cf.: (eum Tiberius) incolumem fore gratatur, Tac. A. 6, 21 fin.: totoque libens mihi pectore grator, Ov. M. 9, 244; cf.: quid tibi grataris? id. H. 11, 65.
Hence, grātanter, adv., with rejoicing, with joy (post-class.): senatus gratanter accepit, Capitol. Macr. 7: accipere, id. Max. 14; Amm. 17, 12; Inscr. Orell. 2588.