noun
Meaning 1
Any set X such that for any x ∈ X, if y ∈ x then y ∈ X; equivalently, such that if x ∈ X and x is not an urelement then x ⊆ X.
Definition source: English Wiktionary via Wiktextract
Topics: mathematics, sciences, set-theory
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided