dud
You can call something that makes something move a "force" or a "mover," while something that causes it to stop can be referred to as a "brake" or a "stopper."
You can call something that is being tested on a "test subject" or a "trial participant."
You call it an OBSERVATION.
Audible.
You would call it a permit or authorization document.
dud
A palindrome for something that fails to work is "bug".
dud
a neep[not able to work
If they do something you know is wrong call them out on it. If all else fails spank them!
That could be dud.
you get a bunch of food that it likes and if that doesn't work call the animal control. if that fails don't ask me.
becuz i work for trayark and they wanted backup if mutiplayer fails so they made zombies
Something you are interested in, or can get interested in. Something you can complete in the time allowed. Something you can be proud of, even if it is an experiment that fails. Science is about finding where what we "know", fails.
i call clumsy Irish dance something you need to work on
it is called a dud.
It survives.