The term reflection (also spelt reflexion) can refer to several different concepts:

• In mathematics, reflection is the transformation of a space.
• In physics, reflection is a wave phenomenon.
• In computer science, reflection is a programming language feature for metaprogramming.
• In .NET, Reflection is a base class in the assembly System, which provides methods of conversion between managed and unmanaged code.
• In electricity, reflection is reflected voltage in an electrical signal due to an impedance change.
• In music, Reflection is a 1998 album by Paradise Lost.
• Reflection is an online game developed by Free Fall Associates
• In psychology, reflection is a process of thoughtful meditation or rumination
• A reflection is one's image as seen in a mirror

In some British spellings, reflection may appear as reflexion.