A papilloma (plural papillomas or papillomata) (papillo- + -oma) is a benign epithelial tumor[1] growing exophytically (outwardly projecting) in nipple-like and often finger-like fronds.

When used without context, it frequently refers to infections (squamous cell papilloma) caused by human papillomavirus (HPV), such as warts.

[2][3][4][5][6] Most viral warts are caused by human papillomavirus infection (HPV),[7] of which there are nearly 200 distinct human papillomaviruses (HPVs),[4] and many HPV types are carcinogenic.

A benign papillomatous tumor is derived from epithelium, with cauliflower-like projections that arise from the mucosal surface.

Immunoperoxidase stains have identified antigens of the human papillomavirus (HPV) types 6 and 11 in approximately 50% of cases of squamous cell papilloma.