Walked in for an introduction (4)
I believe the answer is:
trod
'walked' is the definition.
(treading is a kind of walking)
'in for an introduction' is the wordplay.
'in' indicates a hidden word.
'TROD' is hidden in the letters of 'for introduction'.
(Other definitions for trod that I've seen before include "Pressed (grapes) by foot" , "Took steps" , "Walked upon" , "Crushed (grapes) by foot" , "Stepped heavily" .)