Measure that's right but wrong? (5)
I believe the answer is:
girth
'measure' is the definition.
(I've seen this before)
'right but wrong?' is the wordplay.
'right' anagrams to 'GIRTH'.
But, I'm not sure how the anagram is indicated.
'that's' acts as a link.
Can you help me to learn more?
(Other definitions for girth that I've seen before include "Circumferential measure" , "Size of waist perhaps" , "A band passing under horse's belly" , "The distance around a thing or tummy" , "weighty indication?" .)