Dump plate if damaged (7)

I believe the answer is:

fleapit

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

'dump' is the definition.
Although both the answer and definition are singular nouns, I can't understand how one could define the other.

'plate if damaged' is the wordplay.
'damaged' indicates anagramming the letters.
'plate'+'if'='plateif'
'plateif' anagrammed gives 'FLEAPIT'.

Can you help me to learn more?

(Other definitions for fleapit that I've seen before include "Shabby old cinema" , "jumper" , "Scruffy cinema" , "shabby public building" , "Run-down cinema" .)

I've seen this clue in The Times.

Want a hint initially instead of a full solution? Install my app