functioning (
http://definr.com/functioning)
adj : performing or able to perform its regular function; "a
functioning flashlight" [ant:
malfunctioning]
n : process or manner of functioning or operating; "the power of
its engine determine its operation"; "the plane's
operation in high winds"; "they compared the cooking
performance of each oven"; "the jet's performance
conformed to high standards" [syn:
operation,
performance]