I travel beyond Egyptian capital (3)
I believe the answer is:
ego
'i' is the definition.
(thesaurus)
'travel beyond egyptian capital' is the wordplay.
'travel' becomes 'go' ('go' can be a synonym of 'travel').
'beyond' says to put letters next to each other.
'capital' suggests taking the first letters.
The first letter of 'egyptian' is 'e'.
'go' put after 'e' is 'EGO'.
(Other definitions for ego that I've seen before include "Self-esteem, sense of self" , "Sense of self, conceit" , "Self-esteem or self-importance" , "Conceit - the Latin "I"" , "One's image of oneself" .)