Criticises for entering two seconds late (6)
I believe the answer is:
slates
'criticises' is the definition.
Although both the answer and definition are verbs in their -s form, I can't see how one could define the other.
'entering two seconds late' is the wordplay.
'two seconds' can mean two substitutions for 'second'.
'entering' indicates putting letters inside.
'second' becomes 's' (common abbreviation).
'second' becomes 's' (common abbreviation).
's'+'s'='ss'
'ss' placed around 'late' is 'SLATES'.
'for' is the link.
Can you help me to learn more?
(Other definitions for slates that I've seen before include "Criticises severely using roof coverings" , "Berates with roofing tiles" , "Thin layers of rock for roofing" , "Strongly criticise the roof tiles" , "Abuses with roof tiles?" .)