Derivation is the process of identifying topics, parameters, and/or values by way of “reasoning”. The inputs to the reasoning process are:
1) pre-existing characterizations1 (which might, or might not, have been produced in the context of a conceptual design) and
2) new information that was (for whatever reason) not considered when developing those pre-existing characterizations.
The most common context for derivation is when a set of technical requirements is being assembled, but it can be encountered in other contexts. See also the exegesis on this topic.
Footnotes- That is, those which predated that start of the derivation effort.[↩]