col-lactānĕus

a

lacteo

I. a brother or sister nourished at the same breast, a foster-brother or sister (post-class.); masc., Gai Inst. 1, 39; Dig. 40, 2, 13; Inscr. Orell. 2281 al.; fem., Dig. 34, 4, 30, § 1 al.
Lewis & Short
A Latin Dictionary, 1879
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