Didelphys \Di*del"phys\, n. [NL. See Didelphia.]

(Zool.) Formerly, any marsupial; but the term is now restricted to an American genus which includes the opossums, of which there are many species. See Opossum. [Written also Didelphis.]

See Illustration in Appendix. --Cuvier. [1913 Webster]

Source: The Collaborative International Dictionary of English v.0.48
 

Didelphis

Source: WordNet (r) 2.0
 

Didelphous \Di*del"phous\, n. [NL. See Didelphia.]

(Zo["o]l.) Formerly, any marsupial; but the term is now restricted to an American genus which includes the opossums, of which there are many species. See Opossum. [Written also Didelphis.]

See Illustration in Appendix. --Cuvier.

Source: Webster's Revised Unabridged Dictionary (1913)