Usage patterns
〈場所〉行きbound for 〈place〉
This train is bound for Osaka.
行きに〈動詞〉on the way there, (do something)
I stopped by the bookstore on the way there.
行きの〈物〉the outbound (ticket, train, etc.)
The outbound shinkansen was fully booked.
行きと帰りthe outward and return trips
I took a different route going and coming back.
Expressions
行きがけの駄賃while you're at it; taking the opportunity; on the way 行き違いになるmiss each other; cross in the mail; go astray; go wrong
