I caught bird going round lettuce (7)
I believe the answer is:
iceberg
'lettuce' is the definition.
(I know that iceberg is a type of lettuce)
'i caught bird going round' is the wordplay.
'caught' becomes 'c' (cricket abbreviation).
'bird going' becomes 'grebe' (I can't explain this - if you can you should give a lot more credence to this answer).
'round' says the letters should be written in reverse.
'grebe' written backwards gives 'eberg'.
'i'+'c'+'eberg'='ICEBERG'
Can you help me to learn more?
(Other definitions for iceberg that I've seen before include "shunned by sailors?" , "Titanic sinker - lettuce" , "Frozen shipping hazard" , "that has hidden depths?" , "One destroyed the Titanic" .)