Crossword Genius

Exploited shelter by church only half used (7)

Ross

I believe the answer is:

leeched

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

'exploited' is the definition.
Although both the answer and definition are past participle verbs, I cannot understand how one could define the other.

'shelter by church only half used' is the wordplay.
'shelter' becomes 'lee' (as in lee side, the side sheltered from wind).
'by' means one lot of letters go next to another.
'church' becomes 'ch' (common abbreviation).
'only half' suggests halving the letters.
'used' halved is 'ed'.
'lee'+'ch'+'ed'='LEECHED'

Can you help me to learn more?

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