Unnecessary loss of a point irritates (7)
I believe the answer is:
needles
'irritates' is the definition.
Although both the answer and definition are verbs in their -s form, I can't understand how one could define the other.
'unnecessary loss of a point' is the wordplay.
'unnecessary' becomes 'needless' (similar in meaning).
'loss of' is a deletion indicator.
'a point' becomes 'S' (S is an example).
'needless' with 's' taken away is 'NEEDLES'.
Can you help me to learn more?
(Other definitions for needles that I've seen before include "Winds up" , "Stacks of chalk" , "Pins and - -" , "Western point of the Isle of Wight" , "Teases or provokes with knitting implements" .)