spectralˈity noun

1. The state of being spectral
2. A spectral object

specˈtrally adverb

spectrologˈical adjective

spectrologˈically adverb

spectrolˈogy noun

The study of ghosts

spectre bat noun

A leaf-nosed bat

spectre crab noun

A glass crab

spectre insect noun

A phasmid

spectre lemur noun

The tarsier

spectre shrimp noun

A skeleton shrimp

spectrum /spekˈtrəm/

noun (pl specˈtra)

1. The range of colour produced by a prism or diffraction grating
2. Any analogous range of radiations in order of wavelength
3. The range of frequencies of sound or a sound
4. The range of effectiveness of a drug, esp an antibiotic (pharmacology)
5. A range of opinions, activities, etc (figurative)
6. An after-image

specˈtral adjective

Relating to, or like, a spectrum

spectralˈity noun

specˈtrochemistry noun

Chemical spectroscopy

specˈtrogram noun

1. A photograph of a spectrum
2. A sound spectrogram (see under sound¹)

specˈtrograph noun

A spectroscope designed for use over a wide range of frequencies (well beyond visible spectrum) and recording the spectrum photographically (see also mass spectrograph under mass¹)

spectrographˈic or spectrographˈical adjective

spectrogˈraphy noun

spectrohēˈliogram noun

A photograph of the sun by monochromatic light

spectrohēˈliograph noun

An instrument for taking it

spectrohēˈlioscope noun

A similar instrument with which one can observe an image of the whole solar disc in the light of a single particular wavelength

spectrologˈical adjective

spectrologˈically adverb

spectrolˈogy noun

The science of the spectrum or spectrum analysis

spectromˈeter noun

1. An instrument for measuring refractive indices
2. One used for measurement of wavelength or energy distribution in a heterogeneous beam of radiation (see also mass spectrometer under mass¹)

spectrometˈric adjective

spectromˈetry noun

spectrophotomˈeter noun

An instrument for measuring intensity of each colour or wavelength present in an optical spectrum

spectrophotomˈetry noun

specˈtroscope noun

A general term for an instrument (spectrograph, spectrometer, etc) used in spectroscopy, the basic features of which are a slit and collimator for producing a parallel beam of radiation, a prism or grating for ‘dispersing’ different wavelengths through differing angles of deviation, and a telescope, camera or counter tube for observing the dispersed radiation

spectroscopˈic or spectroscopˈical adjective

spectroscopˈically adverb

spectroscopist /spek-trosˈkə-pist or spekˈtrə-skop-ist/ noun

spectrosˈcopy (or /spekˈ/) noun

The study of spectra

spectral type noun (astronomy)

One of the different groups into which stars can be classified according to characteristics of their spectra

spectroscopic binary noun (astronomy)

A binary star whose components are too close to be resolved visually, but can be resolved spectroscopically

spectrum analysis noun

Determination of chemical composition by observing the spectrum of light or X-rays coming from or through the substance