english
1
general::
Phrase(s): *too good to be true almost unbelievable; so good as to be unbelievable. (*Typically: be ~; become ~; get ~.) • The news was too good to be true. • When I finally got a big raise, it was too good to be true.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
So excellent that it defies belief, as in She loves all her in-laws? That's too good to be true. This term expresses the skeptical view that something so seemingly fine must have something wrong with it. The term was part of the title of Thomas Lupton's Sivquila; Too Good to be True (1580).
American Heritage Idioms