A person who supports or advocates for embargoes as a political or economic strategy.
From embargo + the agent suffix '-ist' (one who practices or believes in something). The '-ist' suffix comes from Latin and Greek and is widely used in English to denote advocates or practitioners of an ideology or activity.
The term 'embargoist' is rare in everyday use, but it perfectly demonstrates how English can create new words on demand by combining roots with standard suffixes—you could theoretically call any activist an '-ist' of their cause.
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