Use 'butt in' when somebody interrupts a smooth conversational flow without waiting for their turn.

Conversation Flow

'Butt in' implies rudeness or lack of manners when interrupting, often perceived negatively.

Negative Connotation

The phrase 'butt in' is informal and should be used mainly in casual conversations or writing.

'Butt in' suggests inserting oneself into a situation without an invitation or need.

Using 'butt in' can indicate a lack of respect for personal boundaries or privacy.

The phrase often relates to offering advice or opinions that nobody asked for during a discussion.