Hors d'œuvres or appetizers were small bite-sized portions of food served with intention of whetting one's appetite for the main course.
In 2371, Neelix and Kes served hors d'œuvre on trays on the bridge. (VOY: "The Cloud")
In 2374, while experiencing a crisis of conscience, The Doctor mentioned not taking any of the canapés offered at Ahni Jetal's birthday party. (VOY: "Latent Image")
In 2376, Neelix offered to make hors d'œuvres for Tom Paris after the latter told him of his plans to christen Alice. (VOY: "Alice")
In 2378, Seven of Nine served braised leeks to a hologram of Chakotay. (VOY: "Human Error")