Incapable of being emotionally moved or persuaded.(adjective)
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Use "unmovable" in a sentence
"The division was "unmovable," and became known as "the rock of the Marne.""
"The demonstrators' energy and numbers were evidence that Egyptians, long frustrated by mounting economic woes and a seemingly unmovable leadership, were capable of uniting to challenge the rule of President Hosni Mubarak."
"Ruggiero has built a reputation as an unmovable force on the American blue line."