Happy Lineker's ignoring tip from Shearer (3)
I believe the answer is:
gay
'happy' is the definition.
(similar in meaning)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for gay that I've seen before include "Brightly coloured" , "Light-hearted, carefree" , "John --, author of 'The Beggar's Opera'" , "Writer of The Beggar's Opera" , "Homosexual" .)