metro- 1
a combining form meaning "measure," used in the formation of compound words: metronome.
[ comb. form repr. Gk métron measure ]
metro- 2
a combining form meaning "uterus," used in the formation of compound words: metrorrhagia.
Also, esp. before a vowel, metr- .
[ comb. form repr. Gk métra womb ]
metro- 3
a combining form representing metropolis or metropolitan in compound words: metroflight; metroland; Metroliner.