Early 13th cent. From Latin lacus
From Proto-Italic *laku-
'id.' From Proto-Indo-European *lok-u̯
'id.' The form is difficult, especially with evidence of a zero-grade in Greek λάκκος (lákkos) "pond," "cistern." To add to the problem, the word looks like a u̯-stem in Proto-Indo-European, yet Proto-Hellenic *-kw-
shouldn't produce geminate -κκ-.
The word is probably a late Proto-Indo-European development or Greek borrowed the word from another Indo-European language. An alternative theory that the word represents an old a-root ablaut (see below) raises more phonological problems than it solves.
Also the origin of the surname del Lago, Lagos and Laguillo.
Western Vulgar Latin: Asturian llagu, Portuguese lago, French lac, Italian lago; Eastern Vulgar Latin: Aromanian lac, Romanian lac; Sardinian: lagu; Extra-Comparanda: Basque lak(h)u "lake"
(borrowed from Latin)
Celtic: Old Irish loch "lake;" Germanic: Old Norse lǫgr "sea," Old High German lahha "puddle," Old Saxon lagu "lake," Old English lagu 'id.;' Balto-Slavic: Old Church Slavonic lokъvi "puddle," BCS lȍkva 'id.;' Hellenic: Ancient Greek λάκκος (lákkos) "lake"
As mentioned above, the word lago
may in fact be a remnant of a Proto-Indo-European ablaut with a root-vowel *a
. This is controversial at best, and not reflected in the etymologies in our dictionary, however the bare possibility demands mentioning.
"Although the evidence is sparse, it appears that roots with a
as fundamental vowel also ablauted. The root *sal-
'salt' had a zero-grad *sl̥-
...; the root *nas-
'nose' has a lengthened-grade derivatives such as Latin nār-ēs
and English nose
, both from *nās-
; and the root *laku-
'body of water' (Lat. lacus
'lake', Gk. lákkos
'pond') had an o-
grade form *loku-
that became Scottish Gaelic loch
'lake'. The view that roots in a
ablauted is not universally accepted, but these forms are difficult to explain otherwise." ~ B. Fortson, Indo-European Language and Culture