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OOAK

The abbreviation OOAK stands for the expression, "one of a kind." The term originates in yachting in 1949 to describe a regatta race in which ship builders were allowed to enter as many different models of yachts into the regatta as they manufactured, but no more than one of each model (hence, "one of a kind").

Since then the term has found different and expanded use as an Internet acronym, especially with regard to the sale of handmade merchandise which is "one of a kind" with respect to actual production rather than to allowed number of entries in a competition. The term has widespread use in the cottage industry of doll making, but is used in any manufacturing sector in which the one-of-a-kind nature of a product signifies its value/importance.