a local cherry-like tree, or the fruit of it (see Molina)
The capolin has trilingual descriptions and an image (of the capolcuahuitl, capolin tree) and the elocapolin in the Digital Florentine Codex. Its fruit is harvested and sold in the tianquiztli.
There are several varieties of capolin. The elocapolin has larger, more sought-after berries. The tlaolcapolin berries are much less desirable, and in fact they are offensive. Similarly, the xitomacapolin is harmful to the stomach, and people avoid it.
See an image that represents capolin in the Visual Lexicon of Aztec Hieroglyphs, ed. Stephanie Wood (Eugene, Ore.: Wired Humanities, 2020-present).
The cacapolton is a small tree with leaves similar to the capolin (or capulin), but the fruit is red, then turns purple, and finally black. The leaves are used for curing tumors, diarrhea, fevers, wounds, and eye inflammation. (Central Mexico, 1571–1615)
Capolin = a "fruit similar in every respect to our cherries—in shape, color and size; in their seeds or pits, and in taste (except that they tend to the taste of mulberries)...The decoction of its bark, after it has been put out in the sun for fifteen days, drunk in the amount of an ounce, cures bloody diarrhea. Ground to powder, the bark removes cloudiness from the eyes, makes sight clear, and cures inflammations." (Central Mexico, 1571–1615)
oyetetl caltin centetlapancali ontetl xacaltin yoan in calacuemitl ypan mani tlapalnopali yoan metl ypan onoc yoan capolime yan onoc yoan capolime = dos aposentos, los de terrado y otro de jacale, y encima de la tierra [solariega] hay nopales de grana y magueyes y árboles de capulín (San Bartolomé Tenango, 1585)