Old men up for dancing with yours truly, Methuselah? (3,2,5)
I believe the answer is:
nom de plume
'methuselah?' is the definition.
Both the definition and answer are singular nouns.
Perhaps they are linked in a way I don't understand?
'old men up for dancing with yours truly' is the wordplay.
'for dancing' is an anagram indicator.
'with' says to put letters next to each other.
'yours truly' becomes 'me' (the person who set this crossword).
'old'+'men'+'up'='oldmenup'
'oldmenup' with letters rearranged gives 'nomdeplu'.
'nomdeplu'+'me'='NOM DE PLUME'
Can you help me to learn more?
(Other definitions for nom de plume that I've seen before include "Assumed name" , "Pen-name" , "Author's pseudonym" , "Pen name" , "False name" .)