👉 Bristlemouth is a term used to describe a person who has a tendency to be very focused and intense, often with little time for relaxation or downtime. It can also refer to someone who tends to become overly focused on a particular task or activity without considering other aspects of the situation. The term was coined by British comedian and television personality Richard E. Grant in his book "Bristleheads," published in 1963, and is often used to describe individuals who are highly