Rationalization (economics), an attempt to change an ad hoc workflow into one based on published rules; also, jargon for a reduction in staff
Rationalisation (mathematics), the process of removing a square root or imaginary number from the denominator of a fraction
Rationalization (psychology), a psychological defense mechanism in which perceived controversial behaviors are logically justified also known as "making excuses"
Post-purchase rationalization, a tendency to retroactively ascribe positive attributes to an option one has selected
Rationalization (sociology), the replacement of traditions, values, and emotions as motives for behavior in society with rational motives
Rationalization, appropriate placement of a factor such as was done with for Heaviside–Lorentz units
