conc▪ Landberg1920 thinks it is onomatopoetic, to be compared to √ḪRː (ḪRR) (↗ḫarra ‘to murmur, bubble, gurgle; to snore’).
▪ Orel&Stolbova1994 derive it from an AfrAs *qor- ‘to shout, say’ (with assumed cognates in Berb, Eg, and some WCh langs).
▪ Tropper2008 considers a possible relation of Ug ḫwr ‘to be weak (horse)’ (and, implicitly, also of Ar ↗ḫawira) with the animal’s uttering such a sound.