Appeaser (noun)

1. A person who tries to pacify or placate someone, especially by making concessions or giving in to demands.
2. A person who tries to avoid conflict or tension by making concessions or giving in to demands.

Origin:

Mid 17th century: from french appaiser, from appaiser "to pacify", from a- (from latin ad "to") + paix "peace".

Examples:

1. The politicians who tried to negotiate with the dictator were often seen as appeasers.
2. The appeaser tried to pacify the angry mob by promising to meet their demands.
3. He was criticized as an appeaser for giving in to the demands of the kidnappers.
4. The appeaser sought to avoid conflict with the neighboring country by making concessions.
5. The appeaser was willing to make any sacrifice in order to maintain peace.