Definition of -ae in English:

-ae

suffix

  • 1Forming plural nouns used in names of animal and plant families and other groups.

    ‘Felidae’
    ‘Gymnospermae’
  • 2Used instead of -as in the plural of many nonnaturalized or unfamiliar nouns ending in -a derived from Latin or Greek.

    ‘larvae’
    ‘alumnae’

Origin

Latin plural suffix, or representing the Greek plural ending -ai.