Fall behind with hesitancy, due to drink (5)
I believe the answer is:
lager
'drink' is the definition.
(lager is a kind of drink)
'fall behind with hesitancy due' is the wordplay.
'fall behind' becomes 'lag' (synonyms).
'with' says to put letters next to each other.
'hesitancy due' becomes 'er' (I can't explain this - if you can you should believe this answer much more).
'lag'+'er'='LAGER'
'to' is the link.
Can you help me to learn more?
(Other definitions for lager that I've seen before include "Tipple" , "Light-coloured beer" , "The drink could be regal" , "Regal sort of beer" , "Light beer; sounds like camp" .)