Illustrated Glossary of Organic Chemistry

Tetrahedral carbon: A carbon atom with four attachments, and bond angles of approximately 109.5^o. The overall shape is that of a tetrahedron (i.e., a pyramid with all faces being equilateral triangles, or nearly so). The carbon atoms uses sp³ orbitals to achieve this geometry. When all four attachments are different, the carbon is a stereocenter.

(R)-Bromochlorofluoromethane. All bond angles approximately 109.5^o.
The carbon has four different attachments, and thus is a stereocenter.