buffoon, joker; or, something that makes someone laugh (see Molina)
Consider also: "Xolopi'tli (~ xolopitli, xolopihtli) 'idiot, fool'.... You can find the term in Frances Karttunen's Analytical Dictionary. For 'crazy' there's a (Zacapoaxtla) dialect term cua:(yo:l)quepi. Then there's Classical Nahuatl i:xtepetla for someone stupid, an ignoramus. Classical te:huetzqui:ti' is 'buffoon, joker'."
"A lot of the indigenous professors at IDIEZ in Zacatecas and I tease each other by saying 'tihuihuiti' or 'tihuihuitic.' Most of them are speakers of eastern (Huastecan) Nahuatl from Veracruz and we've all understood the phrase as either 'you are crazy' or 'you have already turned crazy,' but in a joking and teasing manner, obviously. I hope that helps!"