definition of
testing

[1] #1 testing n. the act of subjecting to experimental test in order to determine how well something works; "they agreed to end the testing of atomic weapons". wn

[2] #2 testing n. an examination of the characteristics of something; "there are laboratories for commercial testing"; "it involved testing thousands of children for smallpox". wn

[3] #3 testing n. [examination] the act of giving students or candidates a test (as by questions) to determine what they know or have learned. wn