1. To take in by a spheroidal body; said of the ingestion of bacteria and other foreign bodies by the phagocytes.
2. To ingest particles by the process of phagocytosis (endocytosis of particulate material; such as, microorganisms or cell fragments).

Endocytosis is medically defined as the uptake by a cell of material from the environment by invagination of its plasma membrane; it includes both phagocytosis and pinocytosis.

A phagocyte is any cell capable of ingesting particulate matter; for example, a microphage, macrophage, or monocyte. Such cells ingest microorganisms and other particulate antigens that are opsonized (coated with antibody or complement), a process mediated by specific cell-surface receptors.