Englishfor English speakers
Ac
—
noun
(= actinium)
a radioactive element of the actinide series; found in uranium ores
AC
—
noun
an electric current that reverses direction sinusoidally
In the US most household current is AC at 60 cycles per second
filter
Noun
—
A filter is a piece of equipment that put gas or liquid through to take out the parts you don't want, to clean it.
Car engines have a fuel filter to keep the fuel clean.
filter
Verb
—
If you filter a gas or a liquid, you put it through something that takes out the parts you don't want.
We filter the water.