Are yams and sweet potatoes the same?
1590s, "mark made on skin by burning with a hot iron," from Latin stigma (plural stigmata), from Greek stigma (genitive stigmatos) "mark, puncture," especially one made by a pointed instrument, from root of stizein "to mark, tattoo," from PIE *st(e)ig- (see stick (v.)). Figurative meaning "a mark of disgrace" is from 1610s. Stigmas "marks resembling the wounds on the body of Christ, appearing supernaturally on the bodies of the devout" is from 1630s; earlier stigmate (late 14c.), from Latin stigmata.
stigma stig·ma (stĭg'mə)
n. pl. stig·mas or stig·ma·ta (stĭg-mä'tə, -māt'ə, stĭg'mə-)
Visible evidence of a disease.
A spot or blemish on the skin.
A bleeding spot on the skin considered as a manifestation of conversion disorder.
The orange pigmented eyespot of certain chlorophyll-bearing protozoa, such as Euglena viridis. It serves as a light filter by absorbing certain wavelengths.
A mark of shame or discredit.
The sticky tip of a flower pistil, on which pollen is deposited at the beginning of pollination. See more at flower.