I'd a strange name for a Welshman (3)
I believe the answer is:
dai
'name for a welshman' is the definition.
(common Welsh name)
'i'd a strange' is the wordplay.
'strange' indicates an anagram.
'id'+'a'='ida'
'ida' with letters rearranged gives 'DAI'.
(Other definitions for dai that I've seen before include "Welshman's name" , "Welshman" , "Perhaps man in Cardiff" , "Short for 'Dafydd'" , "Welsh male name" .)