小哥哥

xiǎogēge
  1. little boy who is older than another young child (e.g. his playmate)
  2. (neologism c. 2017) (slang) amiable form of address for a young man of about one's own age or a little older

CEDICT

neologism slang

Entry Composition

1 小 xiǎo
  1. small
  2. tiny
  3. few
  4. young
2 哥哥 gēge older brother

classifiers: 個, 位