noun
face powder; powdered face powder
Refers specifically to loose or pressed powder used on the face, as opposed to liquid foundation or other cosmetics.
化粧直しに粉白粉を使う。
I use face powder for touch-ups.
おしろい is a general term for face powder, while 粉白粉 specifically emphasizes the powdered form.
Compound of 粉 (kona, 'powder') and 白粉 (oshiroi, 'face powder'). The reading おしろい is a compound of 白 (shiro, 'white') with honorific prefix お.