Girl thought to be like Queen Victoria? (8)
I believe the answer is:
unamused
'be like queen victoria?' is the definition.
(I've seen this before)
'girl thought' is the wordplay.
'girl' becomes 'Una' (girl's name).
'thought' becomes 'mused' (musing is a kind of thinking).
'una'+'mused'='UNAMUSED'
'to' acts as a link.
(Other definitions for unamused that I've seen before include "Not finding things funny" , "Not entertained" , "like Queen Victoria" , "Serious" .)