(ak-sel' -e-ra-tor) [see Acceleration].
1. That which accelerates. 2. A muscle which hastens a physiologic discharge. A. Nerves, nerves passing from the medulla to the heart and conducting stimuli that cause acceleration of the heart's action. A. partus, an abortifacient or ecbolic agent. A. urinse, a muscle of the penis the func- tion of which is to expel the last drops in urination, to expel the semen, and to assist erection. The sphincter vaginae is its ana- log in the female.