mai·a·saur·a 
(mī′ə-sôrə)
(mī′ə-sôrə)n.
A herbivorous hadrosaurid dinosaur of the genus Maiasaura of the Cretaceous Period. Remains of fossilized nests and juveniles suggest that the adults cared for their young.
[New Latin Māiasaura, good mother lizard, genus name : Greek maia, good mother; see mā-2 in the Appendix of Indo-European roots + New Latin saura, feminine of saurus, lizard (from Greek sauros).]