Not in right end of queue? That's weird! (5)
I believe the answer is:
outre
'weird' is the definition.
(synonyms)
'not in right end of queue?' is the wordplay.
'not in' becomes 'out' ('out' is the opposite to 'in').
'right' becomes 'R' (common abbreviation).
'end of' indicates one should take the final letters.
The last letter of 'queue' is 'e'.
'out'+'r'+'e'='OUTRE'
'that's' is the link.
(Other definitions for outre that I've seen before include "Deviating from what is usual" , "Off the wall" , "Strange" , "Far out - in France" , "Highly unusual" .)