Source : Webster's Revised Unabridged Dictionary (1913)

Myomorpha \My`o*mor"pha\, n. pl. [NL., fr. Gr. ?, ?, a mouse + ?
   form.] (Zo["o]l.)
   An extensive group of rodents which includes the rats, mice,
   jerboas, and many allied forms.

Source : WordNet®

Myomorpha
     n : true rats and mice and related rodents [syn: {suborder
         Myomorpha}]