The term for pouring liquid over food as it cooks to keep it moist is basting.
Basting usually involves spooning, brushing, or suctioning a food’s own juices, melted fat, sauce, or marinade over its surface at intervals. It is especially associated with roasting poultry, grilling meat, and rotisserie cooking, where prolonged heat can dry the exterior.
A turkey baster is one familiar tool, but a spoon, ladle, pastry brush, or even a brush of melted butter can do the same job. Basting can add flavor and encourage browning, although repeatedly opening an oven can lower its temperature and may increase moisture loss. It is therefore not identical to braising, which cooks food slowly in a larger amount of liquid, or poaching, which gently cooks food immersed in liquid.
The technique is also used for foods such as barbecue, where sauce is brushed on during cooking. In some recipes, basting is optional because a covered pan, added fat, or controlled oven temperature may preserve moisture more effectively.