To make something rational or more rational.
To remove radicals, without changing the value of an expression or the roots of an equation.
To justify an immoral act, or illogical behaviour. “The process of thought by which one justifies a discreditable act, and by which one offers to oneself and the world a better motive for one's action than the true motive”
To structure something along modern, efficient and systematic lines, or according to scientific principles. This often includes eliminating duplication and grouping like or similar items.
To simplify or organize a process in order to increase its efficiency.
To design and construct the contours of a vehicle etc. so as to offer the least resistance to its flow through a fluid.
To modernise.
On a weather chart, a line that is tangent to the flow of the wind.
A line that is tangent to the velocity of flow of a fluid; equivalent to the path of a specific particle in that flow.