Mid 16th century (in an earlier sense). From post-classical Latin capitellum capital of a column (Vulgate), top of a tool, division or section of a psalm, kind of lye, (in botany) small knob at the end of e.g. a stigma, (in anatomy) capitulum, either from classical Latin caput head + -ellum, or from classical Latin capitulum with suffix substitution. With sense 1 compare earlier capital.