This study in lexical semantics is in line with a descriptive and comparative approach to linguistics. It aims to explore processes through which were created words which refer to or in three indo-european groups of languages (early Indo-Aryan, early greek and early latin), as well as to understand how populations which appear not to have been native a place near what we now call the sea or the ocean termed this natural element as they came upon it over course of their migrations. The methodological and terminological framework for this study is a method typical of structural semantics, componential analysis, which parses structure of meaning of each lexical unit and classifies them. The goal is to offer an exhaustive synchronic study of these words and to elucidate possibility of a common legacy. The three corpora of data belong to archaic linguistic period of their respective cultures and for this investigation present as large and varied a scope in time and space as possible. The ancient indo-aryan corpus consists of six Vedic samhitas (Rksamhitâ, Samaveda, samhitâ, Vâjasaneyi samhitâ, Taittiriya samhitâ, Atharvaveda samhitâ according to shaunaka and paippalâda classifications); greek corpus is made up of Homer's compositions (the Iliad, Odyssey and Hymns) and those of Hesiod (The Theogony, Works and Days, Shield and Other Fragments); latin corpus is comprised of ten authors representative of archaic literature (Livius Andronicus, Ennius, Accius, Pacuvius, Lucilius, Naevius, Plautus, Terence, Cato) and archaistic tradition (Lucretius, De rerum Natura)