subfamily

from WordNet (r) 3.0 (2006)

subfamily
    n 1: (biology) a taxonomic category below a family

from The Collaborative International Dictionary of English v.0.48

Subfamily \Sub*fam"i*ly\, n. (Biol.)
   One of the subdivisions, of more importance than genus, into
   which certain families are divided.
   [1913 Webster]