Definition of histiocytosis in US English:

histiocytosis

noun

Medicine
  • Benign or malignant proliferation of histiocytes; any disorder characterized by this.

Origin

1920s. From histiocyte + -osis, after German Histiocytose.

Pronunciation

histiocytosis

/ˌhɪstɪəsʌɪˈtəʊsɪs/