An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

1) General: (n. & adj.) A whole comprised of many elements. → complex wave.
2) (adj.) Complicated and hard to solve.
3) Math: Pertaining to or using → complex numbers.

From Fr. complexe, from L. complexus "surrounding, encompassing," p.p. of complecti "to embrace, encompass, include," from → com- "together" + plectere "to weave, twine."

Hamtâft, from ham- "together," → com- + tâft past stem of tâftan, tâbidan "to twist, to spin, to bend, to crook," p.p. tâftah "spun, silk or linen cloth," loaned into E. taffeta (from O.Fr. taffetas, from It. taffeta); similarly Gk. tapetion "little carpet" is probably from this Iranian origin (from which tapestry, tapis); Proto-Ir. *tap- "to spin," related to tan-, tanidan "to spin; to stretch," → tension.

A → complex number in which the → real part of the number remains the same, but i is replaced by -i. For example, the complex conjugate of x + iy is x - iy. Same as → conjugate complex number.

→ complex; → conjugate.

A → dynamical variable which has an → imaginary number part.

→ complex; → dynamical; → variable.

The complex notation for the → Fourier series of a function f(x). Using → Euler's formulae, the function can be written in cimplex form as f(x) = Σ c_n e^inx (summed from -∞ to ∞), where the → Fourier coefficients are c_n = (1/2π)∫ f(x) e^-inx dx (integral from -π to +π).

→ complex; → Fourier series.

A fraction in which the → numerator or → denominator, or both, contain fractions. For example (3/5)/(6/7). Also called → compound fraction.

→ complex; → fraction.

A function whose → variables are → complex numbers.

→ complex; → function.

A molecule in the → interstellar medium comprising at least six atoms (e.g. Herbst & van Dishoeck, 2009, ARA&A).

→ complex; → molecule.

Any number of the form u = a + bi, where a and b are → real numbers and i imaginary, i.e. i² = -1.

→ complex; → number.

A → complex molecule containing C, H, O, and N atoms and involved in life developing processes. See also → organic molecule.

→ complex; → organic; → molecule.

Same as → composite population.

→ complex; → population.

A wave that is composed of several frequencies.

→ complex; → wave.

The conjugate of a → complex number, expressed by ū = a - bi. The complex number and its conjugate have the same real part. Same as → complex conjugate.

→ conjugate; → complex; → number.

Any of the largest stellar assemblages consisting of the groupings of → star clusters, → stellar associations, and individual stars with sizes of 300-1000 → parsecs and ages of up to 100 millions years. Most stellar complexes are physical entities containing objects of common origin and are the birth places of most star clusters and associations. The brightest and youngest complexes are well-known stellar superstructures that outline the Galactic → spiral arms, and also include → H II regions, → giant molecular clouds, and → neutral hydrogen clouds (Efremov, Y. N., 1996, The Origins, Evolutions, and Densities of Binary Stars in Clusters, ASP Conf. Series, Vol. 90).

→ stellar; → complex.