The door is alarmed

As a non native speaker the sentence looks normal, it means the door was equipped with an alarm. But when I refered to the dictionary, alarmed means frightened. So, what sentence should be written to replace " the door is alarmed".

Hello Ruslan,

As you have probably learned sometimes there is more than one meaning to a word in English. When working out the meaning you also need to look at the context.

'The burglars decided to move on to the next house because the first one was alarmed.'

'I was alarmed when I saw the way he was driving.' 

Instinct tells me we are more likely to use alarm in the first context than the second these days.

All the best

Bob