deprived of a decent standard of living, education, etc. by poverty and a lack of opportunity; underprivileged
See disadvantaged in American Heritage Dictionary 4
Deprived of some of the basic necessities or advantages of life, such as adequate housing, medical care, or educational facilities.
Being at a disadvantage, especially with respect to competitive or opposing elements or forces: “We can't have . . . disadvantaged conventional forces on one hand and strategic nuclear forces on the other”(Bernard Rogers).
noun(used with a pl. verb)
Deprived people considered as a group. Often used with the.