Definition of Grey Panther in US English:

Grey Panther

(US Gray Panther)

noun

US
  • (In plural) an activist organization in the United States which seeks to promote social justice and the interests and rights of the elderly; (in singular) a member of this organization; (more generally) (chiefly with lower-case initials) an elderly person who is politically or socially active, especially in support of the rights of the elderly.

Origin

1970s; earliest use found in The Los Angeles Times. After black panther.