phagocytosis
Concise Oxford English Dictionary © 2008 Oxford University Press:
phagocytosis /ˌfagə(ʊ)sʌɪˈtəʊsɪs/
▶noun Biology the ingestion of bacteria or other particles by phagocytes and amoeboid protozoans.
– derivatives
phagocytize (or phagocytise) verb,
phagocytose verb.
phagocytize (or phagocytise) verb,
phagocytose verb.
'phagocytosis' also found in these Oxford entries:

