Ρ ρ

indecl., τό
Ρ ρ, ῥῶ, τό, indecl., twentieth (later seventeenth) letter of the Gr. alphabet: as numeral ρ/ = 100, but r' = 100,000: reckoned as a semivowel by Arist. Po. 1456b28: the name ῥῶ occurs in Ar. Th. 781, Callias ap.Ath. 10.453d, Pl. Cra. 426c, BCH 29.483 (Delos), etc.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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