Craving beer at last in the present time (6)
I believe the answer is:
thirst
'craving' is the definition.
(thirst can mean a craving or longing for something)
'beer at last in the present time' is the wordplay.
'at last' indicates one should take the final letters.
'in' is an insertion indicator.
'the present' becomes 'this' (eg this year means the present year).
'time' becomes 't' (abbreviation).
The last letter of 'beer' is 'r'.
'r' inserted inside 'this' is 'thirs'.
'thirs'+'t'='THIRST'
(Other definitions for thirst that I've seen before include "lack of water" , "A need (for liquid)" , "Want of drink" , "Dryness" , "Physiological need to drink" .)