The crossword solution for the term 'As a bug in a rug' is SNUG, which is a four-letter word. SNUG is an adjective that means comfortable and warm, often used to describe a feeling of being safe and secure. It is often used to describe a cozy place or situation, such as being tucked away in a blanket or curled up in a chair. The phrase 'as a bug in a rug' is used to describe someone who is very content and comfortable in their current situation.