Birds of a feather? Lat. columba ‘pigeon, dove’ and Gk. κόλυμβος ‘grebe’

The Latin bird-name columba ‘pigeon, dove’ has often invited comparison with Proto-Slavic *gȍlǫbь ‘id.’, as well as with Greek κόλυμβος ‘grebe, diving bird’. However, the first comparison is formally problematic, while the second one is semantically difficult. The first section of the present paper discusses the etymology and derivational history of Lat. columba, concluding in favor of an IE formation probably parallel to, but not cognate with, the one reflected by Slavic. In the second section, Gk. κόλυμβος is discussed together with the verb κολυμβάω ‘to dive’, showing that the commonly assumed derivation of the latter from the former is unlikely. A new etymology is then proposed for this word-family, arguing that both κόλυμβος < *ḱolum‑gʷ(h₂)‑o‑ and the unattested *κολυμβᾱ‑ < *ḱolum‑gʷ(h₂)‑eh₂‑ inferrable from κολυμβάω arose from the univerbation of a syntagm *ḱolum gʷeh₂- ‘to go covered, to submerge oneself’. These forms would then be coradical of Gk. καλύπτω ‘to cover, hide’, ultimately reflecting the univerbation of a different periphrasis with the same noun *ḱol-u-/*ḱel-u- ‘cover’. The proposed derivation is supported by morphosyntactic parallels across IE and by phraseological collocations of κολυμβάω and καλύπτω in Greek itself.