Discussant (noun)

1. A person who takes part in a discussion or debate, especially in a formal setting.
2. A participant in a discussion or conversation who provides their thoughts or opinions.

Origin:

Early 20th century; earliest use found in the british medical journal. from discuss + -ant.

Examples:

1. The discussant provided insightful commentary during the panel discussion.
2. The discussants had a lively debate about the controversial topic.
3. The discussant was well-prepared and made valid points during the meeting.
4. The discussant's contribution added depth to the discussion.
5. The discussants had differing opinions but remained respectful during the exchange.