Appear scintillating in new singlet (7)
I believe the answer is:
glisten
'appear scintillating in' is the definition.
'glisten' can be an answer for 'appear' (glistening is a kind of appearing). I'm not sure about the 'scintillating in' bit.
'new singlet' is the wordplay.
'new' indicates an anagram.
'singlet' with letters rearranged gives 'GLISTEN'.
Can you help me to learn more?
(Other definitions for glisten that I've seen before include "'Shine, as if wet (7)'" , "Gleam by reflecting light" , "look bright" , "Be a shining example" , "Singlet (anag.); tingles (anag.)" .)