Designed to serve its purpose well, and/or be attractive.

the application of a defined set of cognitive, strategic and practical processes to develop design concepts

Design that is accessible to all, regardless of any disability.

The design of movement in animations / video.

A set of rules on design of buildings and public spaces.

Alternative form of security by design

Of a transport system (such as a road or railway), the assumed vehicle speed used in calculations when designing the system; typically the fastest speed at which it is deemed safe to use the system.

The process of using drawings made by using a computer to design machines, buildings, etc.

(surveying) An optimal network design within a computer. It involves choosing an optimal reference system and revolving it around a certain real number.

(theology) A teleological argument.