definition of
exacting

[1] #1 exacting a. [fastidious] having complicated nutritional requirements; especially growing only in special artificial cultures; "fastidious microorganisms"; "certain highly specialized xerophytes are extremely exacting in their requirements". wn

[2] #2 exacting s. [stern, strict] severe and unremitting in making demands; "an exacting instructor"; "a stern disciplinarian"; "strict standards". wn

[3] #3 exacting s. [exigent] requiring precise accuracy; "an exacting job"; "became more exigent over his pronunciation". wn