One's young; one has to meditate (5)
I believe the answer is:
brood
'to meditate' is the definition.
(brooding is a kind of meditating)
'one's young one' is the wordplay.
I cannot really see how this works, but
'one' could be 'o' (I've seen this in other clues) and 'o' is found within the answer.
The remaining letters 'brod' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'has' is the link.
Can you help me to learn more?
(Other definitions for brood that I've seen before include "Ponder mournfully" , "Clutch" , "Think resentfully about family of children?" , "Collection of chickens" , "Meditate moodily" .)