The 'maillot' (My-O) is the fashion designer's name for a woman's one-piece swimsuit, also now called a 'tank suit' or 'monokini'. A 'maillot' swimsuit generally consists of a tank-style torso top with high-cut legs. However, a 'maillot' may also include a plunging neckline, turtleneck-style top, or revealing cutouts.

The term 'maillot' was inducted into the English dictionary in 1928; it derived from the French phrase for swaddling clothes. In the French language, the word 'maillot' means "shirt" and is used to distinguish leaders in the 'Tour de France'. In colloquial Persian and Arabic, particularly in the Levant region, the term 'maillot' is a generic term used to refer to a swimsuit for both men and women.

In addition to describing women’s one-piece swimsuits, the word 'maillot' has also been used to refer to tights or leotards made of stretchable, jersey fabric, generally used for dance or gymnastics. The term 'maillot' was first used to describe tight-fitting, one-piece swimsuits in the 1920s, as these swimsuits had been manufactured from a similar stretchable, jersey fabric.

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