Row when stopwatch loses minutes? (4)
I believe the answer is:
tier
'row' is the definition.
(a tier is a row of things)
'stopwatch loses minutes?' is the wordplay.
'stopwatch' becomes 'timer' (I've seen this before).
'loses' indicates named letters should be taken away.
'minutes?' becomes 'm' (common abbreviation).
'timer' with 'm' taken away is 'TIER'.
'when' is the link.
(Other definitions for tier that I've seen before include "Rank, level" , "Rank - row" , "Layer, rank" , "Wedding cake layer" , "Storey" .)