1. the right to enter
2. the act of admitting someone to enter

In electrical engineering, admittance is a measure of how easily a circuit or device will allow a current to flow. It is defined as the inverse of impedance. The SI unit of admittance is the siemens (symbol S). Oliver Heaviside coined the term admittance in December 1887. where where Note that (as shown above) the signs of reactances become revers...

• (n.) The act of admitting. • (n.) Permission to enter; the power or right of entrance; also, actual entrance; reception. • (n.) Concession; admission; allowance; as, the admittance of an argument. • (n.) Admissibility. • (n.) The act of giving possession of a copyhold estate. • (n.) The reciprocal of impedance.Admitt...

(from the article `electrical impedance`) ...component of the impedance (whether predominantly inductive or capacitive), the alternating current either lags or leads the voltage. The ...
Found on http://www.britannica.com/eb/a-z/a/20

(Y) Admittance is the measurement of how well a circuit or device allows a current to flow. It is measured in siemens. In the related formulas, its variable is Y
Found on http://www.used-line.com/glossaries/glossary.cfm?g_id=29

(Y) The reciprocal of the impedance. Admittance (Y) consists of two components, the conductance (G) and the susceptance (B). The relationship between Y, G, and B is expressed in complex form as follows: Y = G - iB. (1) The relationship between...

[geophysics] However, the relationship is not a straightforward one of proportionality. Rather, an admittance function is described which is time and frequency dependent in a complex way. ...

Ad·mit'tance noun 1. The act of admitting. 2. Permission to enter; the power or right of entrance; also, actual entrance; reception. « To gain admittance into the house. South. » « He desires admittance to the king. Dryden. » &...
Found on http://www.encyclo.co.uk/webster/A/31

admittance (ad MIT'ns) 1. The right to enter; permission to enter: 'Admittance is by invitation only.' 2. Permission to enter. 3. The right of entry. 4. The measure of how readily an alternating current flows through a circuit; the reciprocal of impedance. It was easy to secure admission to the public library, but she soon found several do...
Found on http://www.wordinfo.info/words/index/info/view_unit/3305/

for a linear two-terminal element or two-terminal circuit with terminals A and B under sinusoidal conditions, quotient of the phasor I representing the electric current in the element or circuit by the phasor UAB representing the voltage between the terminals: where the voltage is the line integral of the electric field stren...
Found on http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-12-51

reciprocal of impedance of stated kind
Found on http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=801-25-15

The ratio of current to voltage, the reciprocal of impedance. The unit of admittance is the siemens (S). Admittance is typically abbreviated as 'y' or 'Y.' See also: Siemens.