Same entry in Photius, Lexicon omicron292 Theodoridis. The headword phrase, in the accusative plural, is taken to be quoted from Plato, Phaedrus 236B (ei)s ta\s o(moi/as laba\s e)lh/luqas), though the scholia there comment on it differently, and there is an earlier instance in Aeschylus, Choephori 498. See generally LSJ s.v. labh/.
For labh/ in other senses, see lambda 3.