(biology) the field of science concerned with processes of communication and control (especially the comparison of these processes in biological and artificial systems)
a high gear used at high speeds to maintain the driving speed with less output power
the state of high or excessive activity or productivity or concentration; "Troops are ready to go into overdrive as soon as the signal is given"; "Melissa's brain was in overdrive"
drive or work too hard; "The teacher is overworking his students"; "Overdriving people often suffer stress"
not subject to the control of the will; "involuntary manslaughter"; "involuntary servitude"; "an involuntary shudder"; "It (becoming a hero) was involuntary. They sank my boat"- John F.Kennedy
controlled by the autonomic nervous system; without conscious control; "involuntary muscles"; "gave an involuntary start"