How did 15th century Dutch “Van Lanckvelt” correspond to neo-Latin “Macropedius”?

Question

The 15th-century Dutch humanist Georgius Macropedius was originally named Joris van Lanckvelt, and his adopted Latin name is generally described as a direct Latinisation of that, without further explanation — but I don’t quite follow how. Joris corresponding to Georgius is standard, and Lanck- (long, tall) becoming Macro- (long, large) seems clear. But how does -velt correspond to -pedius? The only reading for velt I can see is as equivalent to modern Dutch veld (field); meanwhile the only (neo-)Latin readings I can see for pedius would be based on either pes (foot), as in quadruped, or paidea (education, childhood), as in encyclopaedia.

In case it helps to pin down possible alternative readings on the Dutch side, I’ve also seen mentions of a Germanised form von Langefeld (which fits with the reading of velt/feld as field).

Answer 1

It's the Greek word πεδίον (pedion), which means a "plain" or "field." In ancient Greek, it's clearly distinct from παίδιον (paidion), "a little child," from παῖς, παιδός (pais, paidos).

In Medieval Latin, the diphthong /ai/ was reduced to /e/, and by analogy Greek words borrowed into Latin had their /αι/ diphthong reduced to /e/ as well. So the two different roots became homophones in later times. I don't believe we have many (or any?) words derived from πεδίον (pedion), so you won't typically find it in collections of Greek roots.

From παιδός/παίδιον, we also get the Greek word παιδεία (paideia), from which the suffix -pedia (e.g. in "encyclopedia") derives. And that's why you see encyclopaedia as an alternate spelling, but Macropaedius would be an etymological mistake.

This should also not be confused for the Latin root pes, pedis, which does, as you note, mean foot. But usually for names like these, the tendency is to stick to a single language. Since macro- is Greek (magn- would be the Latinized root, like in magnify), so too then should we expect the second element to be Greek. Thus von Königsberg turned into Regiomontanus, with both roots being Latin; for an exception, you have the physician Paracelsus (para- is Greek meaning "next to," celsus is Latin meaning "lofty"), but the celsus element was likely a nod to the Roman medical writer Celsus.