The foote of a verſe, is a meaſure of two ſillables, or of three, diſtinguiſhed by time which is eyther long or ſhort. […] A ſoote^([sic]) of 3. ſillables in like ſorte is either ſimple or myxt. […] The mixt is of 6. diuers ſortes, […] 5. Creticus of a long, a ſhort, and a long, ﹘⏑﹘ daungerous.
Source: wiktionary