Ansuz is the conventional name given to the a-rune of the Elder Futhark, . The name is based on Proto-Germanic *ansuz, denoting a deity belonging to the principal pantheon in Germanic paganism.
The shape of the rune is likely from Neo-Etruscan a (), like Latin A ultimately from Phoenician aleph.
In the Norwegian rune poem, óss is given a meaning of "estuary" while in the Anglo-Saxon one, takes the Latin meaning of "mouth". The Younger Futhark rune is transliterated as àto distinguish it from the new ár rune (á ), which continues the jÃÂran rune after loss of prevocalic *j- in Proto-Norse *jár (Old Saxon ).
Since the name of a is attested in the Gothic alphabet as or , the common Germanic name of the rune may thus either have been *ansuz "god", or *ahsam "ear (of wheat)".
The Anglo-Saxon futhorc split the Elder Futhark a rune into three independent runes due to the development of the vowel system in Anglo-Frisian. These three runes are (transliterated o), "oak" (transliterated a), and "ash" (transliterated æ).
The Younger Futhark corresponding to the Elder Futhark ansuz rune is , called óss. It is transliterated as à. This represented the phoneme /ÃÂÃÂ/, and sometimes /æ/ (also written ) and /o/ (also written ). The variant grapheme became independent as representing the phoneme /ø/ during the 11th to 14th centuries.
It is mentioned in all three rune poems: