Full Idea
Intension cannot be identified with meaning. ..'Cube' and 'regular polyhedron with six square faces' are logically equivalent predicates. The intension is the same (the function giving the cubes in any possible world) but there is a difference of meaning.
Gist of Idea
Intension is not meaning, as 'cube' and 'square-faced polyhedron' are intensionally the same
Source
Hilary Putnam (Reason, Truth and History [1981], Ch.2)
Book Reference
Putnam,Hilary: 'Reason, Truth and History' [CUP 1998], p.27