Proto-Indo-European Roots

Root/Stem: *legh-
Meanings:  to lie
Cognates: Greek lekhos (a couch), lekhetai (he sleeps)
Latin lectus (a bed) > 
Spanish lecho (a bed)
Common Celtic *logó, *legó (I lie), > 
Old Irish lige (a grave), laigim (I lie), Irish Gaelic luighim (I lie), Scottish Gaelic laighim, Welsh gwely (a bed), Cornish gueli, Breton guele, Gaulish legasit (he lies)
Common Germanic *ligjan (to lie), > 
Gothic ligan (to lie), Old English licgan, Old High German liggan, Old Swedish & Old Saxon liggian, Old Frisian liga
Icelandic & Faroese liggja (to lie), German liegen, Danish & Norwegian ligge, Swedish ligga, Afrikaans leg, Dutch liggen
Lithuanian lizdas (a nest) can be a merge of IE *nisdo- & *legh-, meaning 'nest', 'couch', otherwise this initial l- is of unknown origin
Common Slavic *lezjati (to lie), > 
Ukrainian & Serbo-Croatian & Slovene lezhati, Bulgarian lezha (I lie), Macedonian lezham (I lie) Czech lez'eti (to lie), Slovak lez'at', Polish & Upper Sorbian lez'ec', Lower Sorbian lez'es', Russian lezhat' (to lie), lozhe (a couch, a bed)
Notes: Both English lie and lay derive from this very stem. The absence of this one in "Eastern" languages (Indo-Iranian, Tocharic, Anatolian & others) caused some linguists to state that it used to be dialectal in Proto-Indo-European times.