Full Idea
A set is 'dominated' by another if a one-to-one function maps the first set into a subset of the second.
Gist of Idea
A set is 'dominated' by another if a one-to-one function maps the first set into a subset of the second
Source
Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
Book Reference
Enderton,Herbert B.: 'A Mathematical Introduction to Logic' [Academic Press 2001], p.8