Lacking date, one's rejected by Kelly and Irene heartlessly (4,3)
I believe the answer is:
sine die
'lacking date one's rejected by kelly and irene heartlessly' is the definition.
I can't tell whether this definition defines the answer.
'one's rejected by kelly and irene heartlessly' is the wordplay.
'one's' becomes 'I's' (Roman numeral).
'rejected' is a reversal indicator.
'by kelly' becomes 'ned' (outlaw Ned Kelly. I am not sure about the 'by' bit.).
'and' means one lot of letters go next to another.
'heartlessly' means to remove the middle letters.
'irene' with its centre removed is 'ie'.
'is' backwards is 'si'.
'si'+'ned'+'ie'='SINE DIE'
Can you help me to learn more?
(Other definitions for sine die that I've seen before include "without a date" , "Indefinitely (Latin, as applied to sporting suspensions)" , "Postponed indefinitely (L.)" , "For an indefinite period (Latin)" , "indefinitely adjourned" .)