[ rəʊ ]
■ noun the seventeenth letter of the Greek alphabet ( Ρ , ρ ), transliterated as ‘r’ or ‘rh’.
■ symbol ( ρ ) density.
Origin
from Gk.
RHO
Meaning of RHO in English
Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004