A perfume or cologne was a fragrant liquid that was intended to impart its pleasing aroma to people or things.
Aboard the USS Enterprise in 2266, Charles Evans gave a gift of perfume to Yeoman Janice Rand. This kind of perfume was colored green and was Rand's favorite type of perfume. It wasn't available from ship's stores, so she asked Evans where he got it, though he gave her no answer and she hurriedly left to attend to her duties. (TOS: "Charlie X")
Males from Angel I used perfume in spray flacons quite frequently. When Data saw the perfume, he called it "an alcohol-based synthetic, artificially reproducing a floral scent." When asking about the purpose of a perfume, Counselor Troi added that some cultures consider perfume an aphrodisiac. (TNG: "Angel One")
Flaxian assassin Retaya traded with perfumes and had several samples in a case he owned, including perfumes that smelled floral, musky and spicy. By mixing some of the fragrances, he was able to produce a strong poison that would cause a heart attack in those who inhaled the scent. (DS9: "Improbable Cause")