lunette

Lunette, a word borrowed from French, looks like it should mean "little moon" - "luna" being Latin for moon and "-ette" being a diminutive suffix. There is indeed some 17th-century evidence of the word being used for a small celestial moon, but that meaning is now obsolete. Earlier, in the 16th century, "lunette" referred to a horseshoe having only the front semicircular part - a meaning that still exists but is quite rare. "Lunette" has other meanings too rare for our Collegiate Dictionary but included in our Unabridged. Among these are "a blinder especially for a vicious horse" and, in the plural form, "spectacles." ("Lunettes" is the usual term for eyeglasses in modern French.) The oldest meaning of "lunette" still in common use is "something shaped like a crescent or half-moon," which our evidence dates to circa 1639.