*Definition [#o2a8bcd4]
Let X be a compactum i.e. an infinite [[compact]] Hausdorff space.
X is called an AB-compactum if the [[cofinality]] of the [[character]] &ref(http://www.eaflux.com/imgtex/imgtex.fcgi?%5bres=100%5d%7b$%5cchi%20%28x%2cY%29$%7d%25.png); is countable whenever Y is a subset of X and x is a point in Y.

*Reference [#h3bed869]
Isaac Gorelic, Istvan Juhasz, ''AB-compacta'', Comment. Math. Univ. Carolin. 49,1 (2008) 141–146.