Eihwaz (or Eiwaz, Îgwaz) is the Proto-Germanic word for yew, and the reconstructed name of the rune ᛇ. Its is commonly transliterated as ei or ï. Its phonetic value at the time of the invention of the Futhark (2nd century) was not necessarily a diphtong, but possibly a vowel somewhere between [i] and [e], or [æ]. The shape of the rune is the source of some confusion, since it is already similar to the Elder Futhark Sowilo rune, which, after the Eihwaz rune had disappeared, assumed a shape identical to the former Eihwaz rune in the Youger Futhark. For this reason, in the context of Fascist symbolism, the same rune is sometimes referred to as "Sig" (after Guido von List, for Sigel) and as "Eihwaz".

The rune survives in the Anglo-Saxon Futhorc as ᛇ Eoh "yew".

ᛇ Eoh byþ utan unsmeþe treow,

heard hrusan fæst, hyrde fyres,

wyrtrumun underwreþyd, wyn on eþle.

The yew is a tree with rough bark,

hard and fast in the earth, supported by its roots,

a guardian of flame and a joy upon an estate.

The associated letter of the Gothic alphabet is 𐌴 e, named aiƕus.

In the Young Futhark, there is the y-rune ᛦ Yr "yew", but neither its shape nor its sound is related to the Eihwaz rune.

The rune is sometimes associated with the World tree Yggdrasil, which, commonly imagined as an ash, may formerly have been a yew.

In modern systems of runic divination, the Eihwaz rune usually symbolizes death (see also Algiz).