At Lord's, they provide cover for the lower members (4)
I believe the answer is:
'the lower members' is the definition.
Although both the answer and definition are plural nouns, I can't understand how they can define each other.
'at lord's they provide cover' is the wordplay.
'at' is a charade indicator (letters next to each other).
'lord's they' becomes 'ads' (I am not sure about this - if you are sure you should believe this answer much more).
'cover' indicates taking the first letters (in a down clue, the letter covering the word).
The initial letter of 'provide' is 'p'.
'ads' after 'p' is 'PADS'.
'for' acts as a link.
Can you help me to learn more?
(Other definitions for pads that I've seen before include "flats?" , "19 acrosses" , "Treads" , "Quarters" , "tablets" .)