non-functioning
not having a particular purpose:
She is best known for her striking non-functional wall hangings.
A distinction can be made between functional requirements and nonfunctional requirements.
If your connection remains non-functional, try turning your router off and then back on again.
They had to make do with equipment which was often out of date and nonfunctional.
They copied the basic design and just made some minor non-functional modifications.

SMART Vocabulary: related words and phrases

Machines - not functioning
act up
balky
blooey
break down
broken
brokenness
brownout
downtime
fail
flat
malfunction
outage
seize
seize up
short circuit
shot
shudder
shut
shut (something) down
whack

You can also find related words, phrases, and synonyms in the topics:

Unsuitable and unacceptable