Exacting
Pronunciation : Ex*act"ing
Part of Speech : a.
Definition : Defn: Oppressive or unreasonably severe in making demands or requiring the exact fulfillment of obligations; harsh; severe. "A temper so exacting." T. Arnold -- Ex*act"ing*ly, adv. -- Ex*act"ing*ness, n.
Source : Webster's Unabridged Dictionary, 1913
Merriam-Webster's Everyday Language Reference Set: Includes: The Merriam-Webster Dictionary, The Merriam-Webster Thesaurus, and The Merriam-Webster Vocabulary Builder