The Avestan word ašta
Word ašta
Meaning eight, 8
See also Phrygian: ΟΤΥϝΟΙ ‘eight’
Armenian: owt ‘eight’
Lycian: aitãta ‘eight’
Greek: οκτώ ‘eight’
Proto-Indo-European: *hₓok̂tṓ(u) ‘eight’

Other words that might be of interest
aēuua ‘one’, xšuuaš ‘six, 6’, θritiia- ‘third’, paoiriia- ‘first’, paṇca ‘five, 5’, bitiia- ‘second’, hapta ‘seven, 7’, caθβarasca ‘four’