Aleph-null is a mathematical term used to denote the cardinality or the size of a set that is not countable. In simpler terms, it refers to infinity. Synonyms for aleph-null include uncountable, boundless, infinite, endless, limitless, immeasurable, incalculable, inexhaustible, and countless. These words signify the enormity and infinity of the set in question and highlight the fact that it cannot be expressed as a finite number. Aleph-null is a concept that has fascinated mathematicians and scientists for centuries, and its synonyms help to convey the vastness and complexity of the universe we live in.