godan verb (-su), transitive verb
buy again; repurchase; buy a replacement
Used when buying something again, often because the first one was unsatisfactory, broken, or used up.
壊れたので、新しいのを買い直した。
It broke, so I bought a new one.
サイズが合わなかったから、靴を買い直す
The size didn't fit, so I plan to buy the shoes again.