Alacrity :: Alacrity (n.) A cheerful readiness, willingness, or promptitude; joyous activity; briskness; sprightliness; as, the soldiers advanced with alacrity to meet the enemy..
Diacritical :: Diacritical (a.) That separates or distinguishes; -- applied to points or marks used to distinguish letters of similar form, or different sounds of the same letter, as, a, /, a, /, /, etc..
Exacritude :: Exacritude (n.) The quality of being exact; exactness.