paralogy

In biological contexts, this term describes a specific mechanism of evolutionary change. It is a technical term used in genetics and genomics to explain how gene duplication provides the raw material for new biological functions to emerge without sacrificing the original gene's utility.

In the realm of logic and rhetoric, the term carries a negative connotation, referring to a fallacy or a deceptive line of reasoning. It is far less common in modern English than its biological counterpart and is typically reserved for formal philosophical or academic critiques of an argument's validity.