Tuber is more peculiar, cut the wrong way (4)
I believe the answer is:
eddo
'tuber' is the definition.
(I've seen this before)
'more peculiar cut the wrong way' is the wordplay.
'more peculiar' becomes 'odder' (I've seen this in another clue).
'cut' means to remove the last letter.
'the wrong way' says the letters should be written in reverse.
'odder' with its last letter taken off is 'odde'.
'odde' written backwards gives 'EDDO'.
'is' acts as a link.
(Other definitions for eddo that I've seen before include "exotic vegetable" , "elephant's ear" , "Tropical plant" , "taro tuber" , "Tropical corm vegetable" .)