Proposed Canon
"Men" in Erfworld resemble Real World humans, except for their smaller size (when compared to the only known non-native human, Parson Gotti, they appear 1/2 to 3/4 of his height), have larger than normal heads for adult Real World humans, have unique eyes, and the ways in which Erfworld Mechanics create difference between Erfworld situations and corresponding Real World ones. Men qualify as humanoids: "humanoid" is derived from "human" after all.
The name "Men" is generic; they appear in both sexes, despite the fact that new units in Erfworld are created by cities and appear as newly-minted adults. It's possible that Men are less specialized in function than humanoid units of other types.
 Physical Differences
Men in Erfworld have differences in their eyes. Variations in the pupil, iris, and sclera (the "white" of the eye) differentiate humans: these eye differences may indicate the Unit's Tribe, but there are too few examples to compare to be certain. The only known Units of the same tribe -- Stanley and Sizemore of the Plaid Tribe -- with close ups of their eyes are very similar, while very few others have eyes identical to others. Wanda and Jillian have similar eyes -- sclera, iris, no pupil -- but are from different, but potentially related, Tribes, though Wanda's irises are of a very rare light blue coloration, while Jillian's are more commonly blue. Only the non-native Parson Gotti has completely normal eyes: every Erfworlder human has something missing or wrong.
Ansom, Ossomer and Tramennis all have similar features, which may or may not be common to the Jetstone tribe.
Certain Erfworld men have other physical differences, which may or may not be related to their Tribe. For instance, Wanda has a much longer neck than is normal for Earth humans, proportional to her body size (see ), and Prince Ansom has a long neck and large chin. It's not clear how many of these are differences in Erfworld anatomy and how much are artistic style -- Ashna also has a relatively long neck, for instance, if not as exaggerated as Wanda's.