Proto-Indo-European Roots

Root/Stem: *náu-
Meanings:  a vessel, a ship
Hellenic Greek naus, Ionic néus 'ship'
Italic Latin návis 'ship', navigare 'to sail, to navigate'
Celtic Common Celtic *nau-
Old Irish nau 'ship', Welsh noe 'dough-trough'
Indic Sanskrit náus 'boat, ship'
Armenian  Armenian nav 'ship' - was it borrowed from Iranian?
Iranian Avestan naváza 'sailor', Old Persian náviyá 'fleet'
Germanic Common Germanic *nów- 'ship' > 
Old Icelandic (poetic) nór 'ship', Norwegian & Swedish nu, no, Middle Low German nóste 'water trough', Old English nówend, Middle High German nuosch 'trough'
Notes: It was proved that Proto-Indo-European speakers used to live far from the sea. There is even no common word for the term 'sea', it appears only in European dialects. This makes us think that the root above denoted a boat for sailing over rivers and lakes, not really a ship. This is also proven by some Germanic meanings 'trough'. Interesting that the root is absent in Balto-Slavic languages, whose speakers also used to live distantly from any seashores.