Nightguard
/ˈnaɪt.ɡɑːrd/noun
A protective dental device worn during sleep, or a person assigned to guard during the night.
Did you know?The word combines night, from an ancient Indo-European term for darkness, with guard, a medieval borrowing connected to watching and protecting—making its literal history a miniature spell of nighttime defense.
Etymological Timeline
Proto-Indo-European
PIE
*nókʷts
“Night or the period of darkness; the ancient root behind night and several Latin and Greek terms.”
Ancient Greek
Greek
nýx, nykt-
“Night; the form survives in scientific compounds such as nyctophobia.”
Classical Latin
Latin
nox, noctis
“Night; the source of English words such as nocturnal and the noct- element.”
Old English
Old English
niht
“Night, darkness, or nighttime.”
Middle English
Old French
garde
“Protection, guarding, or a watch; borrowed into English from garder, “to guard.””
Modern English
English
night guard
“A guard assigned to nighttime duty; later, especially in medical usage, a device worn at night to protect the teeth.”
Explore more surprising origins