Bird caught in hail, heading for empty space (8)
I believe the answer is:
latitude
'space' is the definition.
(thesaurus)
'bird caught in hail heading for empty' is the wordplay.
I cannot really see how this works, but
'bird' could be 'tit' (tit is a kind of bird) and 'tit' is located in the answer.
'hail' could be 'laud' (I've seen this in another clue) and 'laud' is present in the leftover letters.
'empty' could be 'e' (abbreviation e.g. on guages) and 'e' is found in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
(Other definitions for latitude that I've seen before include "Scope (with parallel circles?)" , "Tolerated extent of freedom" , "London's is about fifty one point five degrees North" , "Imaginary lines, parallel to the equator" , "Imaginery line around the earth" .)