Lady from his neighbouring land mostly going with Welshman, oddly (12)
I believe the answer is:
englishwoman
'lady from his neighbouring land' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'mostly going with welshman oddly' is the wordplay.
'mostly' means to remove the first letter.
'with' says to put letters next to each other.
'oddly' indicates anagramming the letters.
'going' with its initial letter taken away is 'oing'.
'oing' put after 'welshman' is 'welshmanoing'.
'welshmanoing' is an anagram of 'ENGLISHWOMAN'.
Can you help me to learn more?
(Other definitions for englishwoman that I've seen before include "Washing lemon (anag) -- native-born inhabitant of Yorkshire, say" , "Dutch, possibly" , "Lady born in one part of the UK" , "Native or naturalized inhabitant of England" .)