Show off, brag (5)
I believe the answer is:
boast
I believe this is a double definition.
'show off' is the first definition.
(I've seen this before)
'brag' is the second definition.
(to boast is to brag or show off)
(Other definitions for boast that I've seen before include "Brag about sabot" , "something to brag about" , "Expression of excessive pride" , "Show off" , "Talk conceitedly" .)