Definitions for evaluation have a common theme of judging or comparing the worth of something.

There are different types of evaluations. Evaluation can range from being very simple service evaluations to complex evaluative research projects.  Each evaluation will require a different approach depending on the purpose of the evaluation; evidence base, stage of development, context of the service or product, and the resources and timescales for the evaluation.

Evaluations can focus on implementation and learning (formative evaluation), how a service works (process evaluation) or whether it has worked (outcome/summative evaluation) – or all of these aspects over the life cycle of a project.

Source: Evaluation works: https://nhsevaluationtoolkit.net/what-is-evaluation/