Extended Strong's Greek Lexicon (Abbott-Smith based)
myriad
Usage: μυριάς, -άδος, ἡ (μυρίος), [in LXX chiefly for רְבָבָה ;] ten thousand, a myriad: pl., Act.19:19, Rev.5:11 9:16; hyperb., of vast numbers, Luk.12:1, Act.21:20, Heb.12:12, Ju 14.† (AS)