Дмитрий
The difference between mad and crazy. These words are synonyms? Are they interchangeable? 
Apr 1, 2017 7:10 AM
Comments · 4
To describe an eccentric mental state somewhere on a spectrum from mentally ill through to merely goofy and playful, you can use "mad" and "crazy" more or less interchangeably. "Crazy" is the softer option, possibly because "mad" is also used as a synonym for "angry".
April 1, 2017
I just wanted to say that Americans don't use "mad" to mean not right in the head. We use it when we are angry about something. We crazy or loco or mental if someone is not right in the head. 
April 1, 2017
Mad:
British Mentally ill; insane.
‘he felt as if he were going mad’British 

Crazy:
Mentally ill; insane.
‘he felt as if he were going mad’

informal 
Mad, especially as manifested in wild or aggressive behaviour.<ul class="semb" style="margin: 0px 0px 32px; padding: 0px; list-style: none;"><li style="margin: 0px 0px 19px; padding: 0px 0px 0px 24px;">
‘Stella went crazy and assaulted a visitor’
</li></ul>
April 1, 2017
Thank you Steve! Thank you Brian!
April 1, 2017