The Collaborative International Dictionary of English v.0.48:

Paeoniaceae \Paeoniaceae\ prop. n.
   A natural family of perennial rhizomatous herbs and shrubs,
   native to temperate Europe and North America.

   Syn: family Paeoniaceae, peony family.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Paeoniaceae
    n 1: perennial rhizomatous herbs and shrubs; of temperate Europe
         and North America [syn: Paeoniaceae, family
         Paeoniaceae, peony family]