How are the characters in A Raisin in the Sun "undeferred"?
The characters do not allow themselves to be put off from buying a house in a new neighborhood and moving in to the house.
Though not all of the family's various dreams and aspirations come to fruition by the end of the play, the family does come together as a unit, overcoming some of their biggest challenges, and refuses to defer the idea of improving their situation.
For a moment, as the play reaches its climax, the family is poised to defer their hopes. Unexpectedly, however, Walter undergoes a change. He realizes what is at stake and he finds a way to feel and enact pride in such a way as to heal the family. In doing this, Walter takes action.
[Walter] does achieve a sense of himself as an individual with power and the ability to make choices.
Taking action and securing the fulfillment of a simple dream serves to prove that the Younger family has not demurred or deferred under pressure from a society that threatens to keep them dis-empowered and disenfranchised. Challenges remain for the family as the play closes, but as a group they have proven that they are unified and proud enough to solve even the deepest problems that face them.