Unable to be imagined; inconceivable or mind-boggling; beyond belief(adjective)
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Use "unimaginable" in a sentence
"In his TV speech Saturday, Prime Minister Sharaf said Egypt's citizens are "the root of all sovereignty and source of all authority" — a phrase unimaginable in Mubarak's days."
"LOS ANGELES Reuters - Oprah Winfrey received an honorary Oscar for her charitable work on Saturday in what she called an unimaginable moment for a black woman who grew up poor in Mississippi and rose to the top of Hollywood stardom."
"Ms. LOVELUCK: The history of the Atacama Desert is crowned with tragedy, endless strikes, hunger marches, deadly accidents, and miners murdered in unimaginable massacres, all of this as a result of a long list of labor, social and moral injustices against miners."