Poor game is discriminating against oldies (6)
I believe the answer is:
ageism
'discriminating against oldies' is the definition.
I can't tell whether this definition defines the answer.
'poor game is' is the wordplay.
'poor' indicates anagramming the letters.
'game'+'is'='gameis'
'gameis' is an anagram of 'AGEISM'.
Can you help me to learn more?
(Other definitions for ageism that I've seen before include "Discrimination on the basis of the length of one's life" , "Images about prejudice against old people" , "Discrimination against the elderly" , "Prejudice based on advanced years" , "The practice of treating people differently on the basis of longevity" .)