'aleph-zero' originates from Hebrew, specifically the word 'אֶלֶף' (aleph), where 'aleph' is the first letter of the Hebrew alphabet and 'zero' signifies the smallest infinite cardinal number.

'aleph-zero' was introduced by the mathematician Georg Cantor in the late 19th century to denote the cardinality of the set of natural numbers.

Initially, it meant 'the smallest infinite cardinal number,' and this meaning has remained consistent in modern mathematical usage.