See doomster rant terribly -- that could be me (12)
I believe the answer is:
demonstrator
'me' is the definition.
Both the definition and answer are singular nouns.
Perhaps they are linked in a way I don't understand?
'see doomster rant terribly' is the wordplay.
'terribly' indicates anagramming the letters.
'doomster'+'rant'='doomsterrant'
'doomsterrant' anagrammed gives 'DEMONSTRATOR'.
'that could be' is the link.
Can you help me to learn more?
(Other definitions for demonstrator that I've seen before include "showroom car" , "shower" , "Participant in a public protest" , "One who shows how things work" , "Rally participant" .)