Adjective: nonfunctional
- Not having or performing a function
"The nonfunctional decorative buttons served no purpose"
- Not performing or able to perform its regular function
"a nonfunctional valve";
- malfunctioning
See also: amiss, awry, bad, cosmetic, decorative, defective, function, haywire, nonstructural, ornamental, out of whack, purpose, role, run-down, unserviceable, use, wrong
Antonym: functional