necessary
necessary necessary
useless>pointless
Pointless
obsolesce
the oppisite of useful is useless
There are several possible words:For useless meaning valueless, the opposite could be "treasured."For useless meaning not workable, the opposite could be "effective."For useless meaning not required, the opposite could be "necessary."For useless meaning worthless, the opposite could be "practical."For useless meaning inappropriate, the opposite could be "pertinent."For useless meaning unhelpful, the opposite could be "desirable."useful - look it up in a dicitonary and you'll see a picture of me.
difficult demanding
brilliant.
useless
A 7 letter word meaning good for nothing is useless.
dont know
The nine letter word is tolerable.