To deter is defined as to keep someone from completing an action by giving them fear or doubt.(verb)
An example of to deter is for a policeman to stop you to ask questions.
See deter in Webster's New World College Dictionary
See deter in American Heritage Dictionary 4
verb de·terred, de·ter·ring, de·ters verb, transitive
Origin: Latin dēterrēre
Origin: : dē-, de-
Origin: + terrēre, to frighten.
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