- an admitting or being admitted
- permission or right to enter
- Elec. the ratio of effective current to effective voltage in a circuit carrying an alternating current; the reciprocal of impedance, measured in siemens and consisting of conductance and susceptance: symbol, Y
- The act of admitting or entering: approved the admittance of new students into the college.
- Permission to enter: a pass that guarantees admittance to the nightclub.
- Y Electricity The reciprocal of impedance.