# Spectrum

#### Pronunciation

*Canada***IPA:***/ˈspektrəm/**US***IPA:***/ˈspɛkt(ʃ)ɹəm/*- Rhymes: -ɛktrəm

#### Origin

From *Latin* __spectrum__ ("appearance, image, apparition"), from __speciō__ ("look at, view"). (see scope)

## Full definition of spectrum

#### Noun

- Specter, apparition.
*from early 17th c.* - A range; a continuous, infinite, one-dimensional set, possibly bounded by extremes.
**2012, November 7**,*Matt Bai*, Winning a Second Term, Obama Will Confront Familiar Headwinds,*As Mr. Obama prepared to take the oath, his approval rating touched a remarkable 70 percent in some polling — a reflection of good will across the political***spectrum**.- Specifically, a range of colours representing light (electromagnetic radiation) of contiguous frequencies; hence electromagnetic spectrum, visible spectrum, ultraviolet spectrum, etc.
*from later 17th c.* **2010**October 30, Jim Giles,*Jammed!*, in*New Scientist*,Current 3G technologies can send roughly 1 bit of data - a one or a zero - per second over each 1 Hz of**spectrum**that the operator owns.- (
*chemistry*) The pattern of absorption or emission of radiation produced by a substance when subjected to energy (radiation, heat, electricity, etc.). - (
*mathematics, linear algebra*) The set of eigenvalues of a matrix. - (
*mathematics, functional analysis*) Of a bounded linear operator*A*, the set of scalar values λ such that the operator*A—λI*, where*I*denotes the identity operator, does not have a bounded inverse; intended as a generalisation of the linear algebra sense.