Onn is the Irish name of the seventeenth letter of the Ogham alphabet, ᚑ, meaning "ash-tree", which is related to Welsh onn(en), from the root was *ōs-, *osen 'ash'. Its phonetic value is [o]. The letter's Bríatharogam kennings are the following:congnaid ech "wounder of horses" féthem soíre "smoothest of craftsmanship" lúth fían "[equipment] of warrior bands"
