a·leph-null (ä'lěf-nŭl', -ləf-) n. The first of the transfinite cardinal numbers. It corresponds to the number of elements in the set of positive integers. Also called aleph-zero.
a·leph-ze·ro (ä'lěf-zîr'ō, -zē'rō, -ləf-) n. See aleph-null.
aleph-null (ä'lěf-nŭl') Pronunciation Key
The first of the transfinite cardinal numbers, corresponding to the number of elements in the set of positive integers.