Frogs or crocodiles?

HAARETZ: Word of the Day / Tzefarde'a: A weird word for an unimpressive plague. Could it be that the rabbis have had it wrong all these centuries, and the plague was actually of crocodiles? Short answer: probably not. As the article notes, the evidence for the meaning "frog" goes back to the Septuagint, whereas the suggestion of the meaning "crocodile" is medieval.

The [five-letter-root] Hebraic word is also pretty unique among the Semitic languages, whose words for "frog" are similar – but only slightly so. Arabic has ḍifda, Aramaic has orda’a, Ge'ez has karn’na’at, while old Egyptians called the pop-eyed amphibian the krar.

As this is the case, how can we be sure that the plague of frogs was really a plague of frogs, especially since the word only appears in the Bible in relation to the same plague and in no other context?

The answer is that we can’t be entirely sure. In fact, in the 12th century Rabbi Abraham Ben Meir Ibn Ezra suggested tzefarde'a actually means "crocodile." That would surely have been much worse than a plague of frogs.