men·tal 
/ˈmɛntl̟/ adjective
/ˈmɛntl̟/ adjective 1 a : of or relating to the mind
▪ mental abilities ▪ She was worried about her son's mental and physical development. ▪ the mental state/condition of a criminal ▪ mental health
b : existing or happening in the mind
▪ We had a mental image/picture of what we thought the house would look like. ▪ I've got a mental list of the things I need at the store. ▪ I'll make a mental note to see if we can reschedule the meeting. ▪ mental arithmetic [=arithmetic done in your mind without writing numbers or using a calculator] 2 always used before a noun a : relating to or affected by an illness of the mind
▪ She was beginning to show signs of mental illness. ▪ a mental disorder ▪ He suffered a mental breakdown. ▪ a mental patient
b : caring for people with mental illnesses
▪ mental hospitals 3 informal : crazy
▪ She looked at me as if I had gone mental. ▪ That guy is a complete mental case. [=he is crazy]
▪ mental abilities ▪ She was worried about her son's mental and physical development. ▪ the mental state/condition of a criminal ▪ mental health
b : existing or happening in the mind
▪ We had a mental image/picture of what we thought the house would look like. ▪ I've got a mental list of the things I need at the store. ▪ I'll make a mental note to see if we can reschedule the meeting. ▪ mental arithmetic [=arithmetic done in your mind without writing numbers or using a calculator]
▪ She was beginning to show signs of mental illness. ▪ a mental disorder ▪ He suffered a mental breakdown. ▪ a mental patient
b : caring for people with mental illnesses
▪ mental hospitals
▪ She looked at me as if I had gone mental. ▪ That guy is a complete mental case. [=he is crazy]
— men·tal·ly adverb
▪ mentally ill ▪ mentally competent ▪ Mentally I'm OK, but physically I'm a wreck!
▪ mentally ill ▪ mentally competent ▪ Mentally I'm OK, but physically I'm a wreck!
