1. (noun) someone who demonstrates an article to a prospective buyer

• sales demonstrator

2. (noun) someone who participates in a public display of group feeling

• protester

1. (noun) someone who participates in a public display of group feeling

• counterdemonstrator
• picket

1. (noun) a teacher or teacher's assistant who demonstrates the principles that are being taught

• instructor
• teacher

2. (noun) someone who demonstrates an article to a prospective buyer

• sales rep
• sales representative
• salesperson

3. (noun) someone who participates in a public display of group feeling

• crusader
• meliorist
• reformer
• reformist
• social reformer

1. (noun) a teacher or teacher's assistant who demonstrates the principles that are being taught

• demo
• demonstrate
• exhibit
• present
• show

2. (noun) someone who participates in a public display of group feeling

• demonstrate
• march
• dissent
• protest
• resist
• protest