Test is a noun meaning a procedure intended to establish the quality, performance, or reliability of something, especially before it is taken into widespread use.
As a verb, test means to take measures to check the quality, performance, or reliability of (something), especially before putting it into widespread use or practice.
The term "test" also refers to:
1. A short written or spoken examination of a person's proficiency or knowledge
2. An event or situation that reveals the strength or quality of someone or something by putting them under strain
3. In chemistry, a procedure employed to identify a substance or to examine the composition of a material