Chiral
/ˈkaɪrəl/noun
Having a structure that cannot be superimposed on its mirror image, like a left hand and a right hand.
Did you know?Lord Kelvin introduced “chiral” in 1894, borrowing the Greek word for hand to describe molecules with distinct left- and right-handed forms.
Etymological Timeline
Ancient Greek
Greek
χείρ (kheír)
“Hand; the physical model for left-right asymmetry”
Classical Greek
Greek
χειρικός (kheirikós)
“Of or relating to the hand”
Late Greek and Latin scientific vocabulary
Greek/Latin
chir- / cheiro-
“Hand, used as a combining form in technical words”
1894
English
chiral
“Coined by William Thomson, Lord Kelvin, for a form that is not superposable on its mirror image”
Modern English
English
chiral
“Having handedness; especially used of molecules, crystals, and geometric objects”
Explore more surprising origins