Short word some feel bally son omitted to send back (12)
I believe the answer is:
monosyllable
'short word' is the definition.
'monosyllable' can be an answer for 'word' (monosyllable is a kind of word). I am not sure about the 'short' bit.
'some feel bally son omitted to send back' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'to send back' is a reversal indicator (I've seen 'sends back' mean this).
'elballysonom' can be found hidden inside 'feel bally son omitted'.
'elballysonom' written backwards gives 'MONOSYLLABLE'.
Can you help me to learn more?
(Other definitions for monosyllable that I've seen before include "Word such as "yes" or "no"" , "Moll's baloney (anag.)" , "Briefest possible utterance" , "Short word, such as "short" or "word"" , "Word of one sound unit" .)