What is a return towards some ancestral type or character; atavism. Reversion of series (Alg.), the act of reverting a series. See To revert a series, under Revert, v. t called?

reversion — (Biol.) A return towards some ancestral type or character; atavism. Reversion of series (Alg.), the act of reverting a series. See To revert a series, under Revert, v. t. (Webster's 1913.)

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