Nod off in a streetcar by accident (2,6)
I believe the answer is:
at random
'accident' is the definition.
Both the answer and definition are singular nouns.
Perhaps they are linked in a way I don't understand?
'nod off in a streetcar' is the wordplay.
'off' indicates an anagram.
'in' means one lot of letters goes inside another.
'streetcar' becomes 'tram' (synonyms).
'nod' is an anagram of 'ndo'.
'a'+'tram'='atram'
'ndo' going into 'atram' is 'AT RANDOM'.
'by' is the link.
Can you help me to learn more?
(Other definitions for at random that I've seen before include "willy-nilly" , "Haphazard" , "In no prearranged order" , "without purpose" , "without prior arrangement" .)