noun
denumerable set; countable set
Technical term in set theory; a set whose elements can be put into a one-to-one correspondence with the natural numbers. See also 可算集合.
See also: 可算集合
有理数全体の集合は可付番集合である。
The set of all rational numbers is a countable set.
Synonym; both mean 'countable set'. 可付番集合 is less common and more explicitly refers to the possibility of numbering the elements.
Compound of 可 (possible), 付番 (numbering), and 集合 (set). A calque from English 'denumerable set' or 'countable set'.