Crossword Genius

Silly birds? (5)

Ross

I believe the answer is:

loons

I'm a little stuck... Click here to teach me more about this clue!

'birds?' is the definition.
(loon is a kind of bird)

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for loons that I've seen before include "Birds" , "of similar type to 2 down [NUMBSKULL]?" , "Casual bags" .)

I've seen this clue in The Independent.
Want a hint initially instead of a full solution? Install my app