Indo-European etymology :

Proto-IE: *ēl-

Nostratic etymology:

Meaning: to burn (tr.)

Old Indian: alāta- n. `firebrand, coal', úlmuka- n. `firebrand, piece of burning charcoal'

Germanic: *ḗl-ia- vb., *ḗl-ō f., *al-a- (˜ -ō-) vb.

Latin: adoleō, -ultum `verbrennen', adolēscō `auflodern', pl. altāria, -ium; ? altāre, -is n. `Aufsatz auf dem Opfertisch, Opferherd, Brandaltar' (may be < altus `high')

Other Italic: Umbr uřetu `(ad)olētō'

Russ. meaning: жечь

References: WP I 88