This paper investigates Lightbody and Berman’s proposal to introduce a new misjudgment of analogical reasoning (Lightbody and Berman 2010): the Metaphoric Fallacy to a Deductive Inference (MFDI). These authors see it as a special case of false analogy fallacy. However, in some relevant cases, the kind of fallacy involved is better deemd as an equivocation fallacy, that is, quaternio terminorum. Therefore, there are no sufficient grounds to introduce a new fallacy. the article presents some basic notions, followed by the structure of analogical reasoning and fallacious analogical arguments, the quaternio terminorum, Lightbody and Berman’s proposal and full argument.