Reconstruction:Proto-Indo-European/h₁éḱwos

Alternative reconstructions

 * *éḱwos
 * *h₁éḱus

Etymology
Usually explained as a derivation of the adjective, also seen in e.g. Ancient Greek , Latin and Sanskrit  (all < PIE ). The thematic derivation would express association with a root noun, thus denoting “that which has swiftness” or “the swift one”. The adjective would have to be derived from the root by reduplication, which is unusual in PIE nominal word formation. Many linguists therefore reject it as popular etymology and suggest other sources: The original thematic form is also disputed. According to Kloekhorst (2008), the original derivation was a u-stem, to which Anatolian reflexes point particularly, which presume a Proto-Anatolian u-stem, as opposed to the thematic (o-stem) derivation in all the other PIE branches. There is no known phonological development through which PIE  could yield PAnat. , and in view of the productivity of the o-stem inflection in Anatolian it is unlikely that PIE would have yielded PAnat. through secondary developments. We therefore must conclude that the Proto-Anatolian u-stem reflects the original state of affairs and that the thematicization as visible in the non-Anatolian IE languages (which would be a trivial development) must be regarded as a common innovation of them. In other words, this is a piece of evidence supportive of the Indo-Hittite hypothesis. In that case, the original paradigm would have been, , , from the stem.
 * Kulanda 2008 argues that the PIE word is borrowed from 🇨🇬; compare 🇨🇬, 🇨🇬, 🇨🇬, 🇨🇬, 🇨🇬 etc. (NCED 520). This etymology has been criticized by Matasović 2012:291 who argues that the direction of borrowing is probably from PIE into North Caucasian: steppe horses were probably traded for Mesopotamian imports on the North Caucasus in the Eneolithic period. The fact that we find fricatives and affricates in the Caucasian reflexes of this word indicates that the source could have been an IE dialect of the satem type.
 * Blažek 2019 proposes that PIE is borrowed from 🇨🇬- "male horse"

Noun

 * 1)  stallion, horse

Descendants

 * (only attested with Sumerogram)
 * Luwian:
 * Cuneiform Luwian: ,
 * Hieroglyphic Luwian: (EQUUS-sa)
 * Armenian:
 * Armenian:
 * Armenian: