Rearer n. : One who, or that which, rears.

Example:
my new horse reared today when we rode away from her friends,is she jst testing me?

Taxonomy
rear, Merriam-Webster Online Dictionary, Dictionary, raise, webster, rearer, Old English, Word Games, Webster Online Dictionary with audio pronunciations, horse, hind, thesaurus, Middle English, glossary, english, language, ESL, Search.

Defination from the web:
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