Cross new wife briefly chasing gutless hubby (6)
I believe the answer is:
hybrid
'cross' is the definition.
(thesaurus)
'new wife briefly chasing gutless hubby' is the wordplay.
'new wife' becomes 'bride'.
'briefly' means to remove the last letter.
'chasing' is a charade indicator (letters next to each other).
'gutless' says to hollow out the word (remove centre letters).
'hubby' with its centre taken out is 'hy'.
'bride' with its last letter taken away is 'brid'.
'brid' after 'hy' is 'HYBRID'.
(Other definitions for hybrid that I've seen before include "Amalgam" , "Crossbreed or mixture" , "Cross of two different species or varieties" , "Crossbred" , "Crossed offspring" .)