In brief, given to being low on staff (5-6)
I believe the answer is:
short-handed
'low on staff' is the definition.
Both the answer and definition are adjectives. Maybe you can see a link between them that I can't see?
'in brief given' is the wordplay.
'in brief' becomes 'short' (similar in meaning. I am not sure about the 'in' bit.).
'given' becomes 'handed' ('hand' can be a synonym of 'give').
'short'+'handed'='SHORT-HANDED'
'to being' acts as a link.
Can you help me to learn more?
(Other definitions for short-handed that I've seen before include "needing more staff" , "need of more staff" , "Not having enough staff" , "Lacking sufficient staff" .)