IPA: /ˈoʊvərˌbaɪ/
KK: /oʊvərˈbaɪ/
To purchase more of something than is necessary or reasonable.
During the sale, many people tend to overbuy items they don't really need.
Past: overbought
Past Participle: overbought
Overbuy → It is formed from "over-" (meaning excessively) and "buy" (from Old English "bycgan", meaning to purchase). The word "overbuy" means to purchase excessively or more than needed.
Think of buying something 'excessively' ('over-') — that's why overbuy means to buy too much.