Final answer:
A single-issue movement is a political movement that focuses on one major issue and lasts for a short amount of time.
Step-by-step explanation:
The type of political movement that focuses on one major issue and lasts for a short amount of time is known as a single-issue movement. These movements revolve around a specific controversial issue or cause and aim to bring about change in that specific area. Examples of single-issue movements include organizations like the National Rifle Association, which focuses on gun rights, or the movement for same-sex marriage/gay rights. These movements tend to have a shorter lifespan compared to broader ideological parties and have a narrow focus on a single issue.