Other forms: mares
A mare is a fully grown female horse. A grey mare, the mare foaled, brood mare.
The words divide by age and sex: a mare is an adult female, a filly a young one, a stallion an uncastrated male and a gelding a castrated one. A brood mare is kept for breeding. The word is unrelated to the mare in nightmare, which meant an evil spirit.
1nounmareAn adult female horse.
“The mare stood in the field with her young foal beside her.”
mare is a horse.
Old English miere names the female horse, from a Germanic root. The mare in nightmare is a different word meaning a crushing spirit.
Proto-Indo-European
*márkos — horse
Proto-Germanic
*marhijō — female horse
Proto-West Germanic
*marhijā
Old English
mīere — female horse, mare
Middle English
mare
English, today
mare
Built from
From Middle English mare, meare, meir, mer, mere, meyre, mure, from Old English mīere (“female horse, mare”), from Proto-West Germanic marhijā, from Proto-Germanic marhijō (“female horse”), from marhaz (“horse”), from Proto-Indo-European márkos (“horse”). 2 Cognate with Scots mere (“mare”), stq Märe (“mare”), West Frisian merje (“mare”), Dutch merrie (“mare”), German Mähre (“female horse”), Danish mær (“old mare”), Faroese mer (“mare”), Icelandic meri (“mare”), Norwegian Bokmål and Norwegian Nynorsk merr (“mare”), Swedish mæhr, mær, mähr, märr (“mare”); also Breton marc'h (“horse”), kw margh (“horse”), Irish and Scottish Gaelic marc (“horse”), Welsh march (“horse”).
Etymology from Wiktionary, CC BY-SA