0 ADJ
The main thing is the most important one of several similar things in a particular situation.
...one of the main tourist areas of Amsterdam...
My main concern now is to protect the children...
1 PHRASE
If you say that something is true in the main, you mean that it is generally true, although there may be exceptions.
Tourists are, in the main, sympathetic people...
In the main, children are taboo in the workplace.
2 N-COUNT
The mains are the pipes which supply gas or water to buildings, or which take sewage away from them.
...the water supply from the mains...
The capital has been without mains water since Wednesday night.
3 N-PLURAL
The mains are the wires which supply electricity to buildings, or the place where the wires end inside the building.
...amplifiers which plug into the mains...
Make sure plugs are disconnected from the mains...
There is relatively little information about main, maybe you can watch a bilingual story to relax your mood, I wish you a happy day!