Around lake there's poor protection (7)
I believe the answer is:
shelter
'protection' is the definition.
(shelter is a kind of protection)
'around lake there's poor' is the wordplay.
'around' indicates putting letters inside.
'lake' becomes 'l'.
'poor' indicates an anagram.
'theres' anagrammed gives 'sheter'.
'l' inserted into 'sheter' is 'SHELTER'.
(Other definitions for shelter that I've seen before include "Protection; charity for the homeless" , "Give protection" , "Shield as from rain" , "retreat" , "Monk's hood" .)