• Cardinal number
• Cardinality

A

• Aleph number
• Amorphous set

B

• Beth number

C

• Cantor's diagonal argument
• Cantor's paradox
• Cantor's theorem
• Cardinal and Ordinal Numbers
• Cardinal assignment
• Cardinal characteristic of the continuum
• Cardinality of the continuum
• Cichoń's diagram
• Cofinality
• Continuum function
• Continuum hypothesis
• Countable set

D

• Dedekind-infinite set

E

• Easton's theorem
• Equinumerosity

F

• Finite set
• Cardinal function

G

• Gimel function

H

• Hartogs number

I

• Infinite set

K

• König's theorem (set theory)

L

• Limit cardinal

N

• Natural number

R

• Rathjen's psi function
• Regular cardinal

S

• Schröder–Bernstein theorem
• Second continuum hypothesis
• Singular cardinals hypothesis
• Strong partition cardinal
• Successor cardinal
• Suslin cardinal

T

• Tarski's theorem about choice
• Tav (number)
• Θ (set theory)
• Transfinite number

U

• Uncountable set

V

• Von Neumann cardinal assignment

W

• Weak continuum hypothesis