A degenerative disease or condition is one that gets worse as time progresses. degenerative diseases of the brain, like Alzheimer's. a degenerative illness gradually gets worse and cannot be stopped progressive
{s} tending to cause progressive deterioration of mental and physical functioning (i.e. degenerative disease)
of illness; marked by gradual deterioration of organs and cells along with loss of function; "degenerative diseases of old age"