in-geniculo, āvi, ātum, 1, v. a. in-geniculum, to cause one to bend the knee; hence, ingeniculare se, to bend the knee, to sink down on the knee, to kneel, Hyg. Astr. 2, 6, fin.; also, without se, Lampr. Elag. 5, 4.
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Hence, ingeniculātus, a, um, P. a., kneeling: Hercules, a constellation, also called ingeniculus, Vitr. 9, 6.