Generally speaking, a sacrificial lamb is a metaphorical reference for a person who has no chance of surviving the challenge ahead, but is placed there for the common good.

In politics, a sacrifical lamb candidate is a candidate chosen to contest an election despite the fact that he or she has little chance of victory. The political party thus appoints the person as a sort of "sacrifice" to the stronger opponent.

In some cases fielding a sacrificial lamb candidate can serve as an opportunity for the party to be more creative in choosing a candidate than would normally be considered acceptable in a closely contested race. For example, they may choose a racial or ethnic minority or a person who would otherwise be considered "too risky" in normal circumstances. For instance, Alan Keyes, Michael Dukakis, or Geraldine A. Ferraro.

In cinema and literature, the term sacrificial lamb refers to a supporting character whose sole dramatic purpose is to die, thus spurring the main character to action. Very often, the sacrificial lamb is a family member, partner, or "old buddy" of the main character, with whom he or she has an assumed intimacy, requiring no real character development. The term is almost always used critically, with the implication that the character was used transparently as a plot device.

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