mental

1. ADJ : ADJ n.

Mental means relating to the process of thinking.

• the mental development of children.     
• intensive mental effort.
• mentally ADV: 
  I think you are mentally tired.    
  Physically I might not have been overseas but mentally and spiritually I was with them.

2. ADJ : ADJ n.

Mental means relating to the state or the health of a person's mind.

• The mental state that had created her psychosis was no longer present.    
• mental health problems.
• mentally ADV :     
  an inmate who is mentally disturbed.     
  the needs of the mentally ill and the mentally handicapped.

3. ADJ : ADJ n.

A mental act is one that involves only thinking and not physical action.

• Practise mental arithmetic when you go out shopping. 
• mentally ADV: 
  This technique will help people mentally organize information.

..... Cobuild

1. of, done by, or involving the mind: mental alertness

2. done in the mind without using speech or writing: mental arithmetic

..... Collins Essential