The definition of an ignoramus is someone who lacks knowledge or is dumb.
(noun)An example of an ignoramus is someone who doesn't know their left from their right.
See ignoramus in Webster's New World College Dictionary
noun pl. ignoramuses
Origin: < the name of a lawyer in Geo. Ruggle's play Ignoramus (1615); L, lit., we take no notice (a legal term formerly written on a bill of indictment by a grand jury that finds it to be not a true bill)
See ignoramus in American Heritage Dictionary 4
noun pl. ig·no·ra·mus·es
Origin:
Origin: From New Latin ignōrāmus, a grand jury's endorsement upon a bill of indictment when evidence is deemed insufficient to send the case to a trial jury
Origin: , from Latin, we do not know
Origin: , first person pl. present tense of ignōrāre, to be ignorant; see ignore
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