The process of absorption of solid food by an ordinary amoeba is called …

This process is called phagocytosis. The amoeba, having found prey, grabs a solid particle (food) with its pseudopods, gradually immersing it inside the cell. As a result, a particle surrounded by a membrane ends up in the cytoplasm of the amoeba. Further, a vacuole is formed around it, which is responsible for digestion. It dissolves and decomposes the particulate matter if possible. Digested food is absorbed by all organelles of the amoeba. Undigested residues, or, if the solid particle does not lend itself to digestion, all this is removed by the vacuole outward, through the membrane.