Solemn cry for Queen Elizabeth (5)
I believe the answer is:
sober
'solemn' is the definition.
(I know that solemn can be written as sober)
'cry for queen elizabeth' is the wordplay.
'cry' becomes 'sob' (sobbing is a kind of crying).
'for' means one lot of letters go next to another.
'queen elizabeth' becomes 'ER' (abbreviation for Elizabeth Regina).
'sob'+'er'='SOBER'
(Other definitions for sober that I've seen before include "Dignified and sombre in manner or character" , "Serious; muted in colour" , "Serious or solemn and not drunk" , "Abstinent" , "Restrained, grave" .)