Felt upset when dismissed or omitted (4,3)
I believe the answer is:
left out
'omitted' is the definition.
(I've seen this in another clue)
'felt upset when dismissed' is the wordplay.
I cannot quite understand how this works, but
an anagram of 'felt' is 'left' which is located in the answer.
'dismissed' could be 'out' (dismissed in cricket) and 'out' is located in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
'or' is the link.
Can you help me to learn more?
(Another definition for left out that I've seen is " Omitted".)