Explanation:

- Usher refers to someone who shows people to their seats in a theater, at a wedding, or other events.

- Option 1: Washerman – A person who washes clothes. This is not relevant to the meaning of usher.

- Option 2: One who uses bad words – This option is not related to usher. This could be considered someone who is abusive or uses profanity.

- Option 3: Soldier – A person who serves in an army. This does not align with the responsibilities of an usher.

- Option 4: Door keeper – This is a person who manages entry to an event, aligning closely with the concept of guiding or ushering people to a location.