The range of conditions classified as pervasive developmental disorders, generally held to include autistic disorder, Asperger syndrome, and pervasive developmental disorder - not otherwise specified (PDD-NOS). Also includes childhood disintegrative disorder and Rett syndrome.

Synonym of autism spectrum

plural of spectrum disorder

plural of light spectrum

(quantum mechanics) A concept relating to energy spectra. Let H be the one-dimensional Schrödinger equation operator H=-(d²)/(dx²)+U_𝛼, where U_α is a periodic function of period α. The Bloch spectrum of H is the set of values E for which all the solutions of (H − E)φ = 0 are bounded on the whole real axis.

plural of political spectrum

The various political viewpoints represented as a continuum, ranging from the extreme left to the extreme right.

plural of optical spectrum

(pharmacology) Any antibiotic that is active against a wide range of bacteria, especially against both gram-positive and gram-negative bacteria.

A form of electromagnetic communication in which the signal frequency or bandwidth is spread beyond that required, rendering it more difficult to intercept or jam, or to send multiple signals over the same band