chromatic

Etymology 1

Borrowed from French chromatique (“chromatic”) or directly from its etymon Latin chrōmaticus, from Ancient Greek χρωματικός (khrōmatikós, “relating to colour; one of the three types of tetrachord in Greek music”), from χρῶμα (khrôma, “colour; pigment; chromatic scale in music; music”) (ultimately from Proto-Indo-European *gʰer- (“to grind; to rub; to stroke; to remove”), perhaps in the sense of the grinding of pigments) + -τῐκός (-tikós, suffix forming adjectives); analysable as chroma + -tic.

adj

1. Uses relating to colour
   1. (not comparable) Characterized or caused by, or relating to, colour or hue.
   2. (comparable) Brightly coloured; colourful, vivid.
   3. (not comparable, optics) Having the capacity to separate spectral colours by refraction.
2. (not comparable, music)
   1. (Ancient Greece, historical) One of three types of tetrachord (the others being the diatonic and enharmonic), with an interval between half and four-fifths of the total interval of a tetrachord.
   2. Relating to or using notes not belonging to the diatonic scale of the key in which a passage of music is written.
      All the intervals of the scale that are a whole tone (step) distant from each other may be divided into half tones, (small steps), forming an entire scale of small intervals, (half tones), called the Chromatic Scale. […] All the tones (steps) of the scale being thus divided, either by means of the sharp or flat, we shall have for our Chromatic Scale thirteen intervals, of a half tone (small step) each. 1853, William B[atchelder] Bradbury, George F[rederick] Root, assisted by Thomas Hastings, T[imothy] B. Mason, “The Singing Class”, in The Shawm: Library of Church Music:[…], New York, N.Y.: Mason Brothers,[…], →OCLC, lesson VIII (Dynamics (Power of Sounds)), page 23, column 1

Etymology 2

From chromatin + -ic (suffix meaning ‘of or pertaining to’ forming adjectives from nouns).

adj

1. (biology) Relating to chromatin (“a complex of DNA, RNA, and proteins within the cell nucleus out of which chromosomes condense during cell division”).
   Each nucleus has, then, (1) a protoplasmic body, and (2) a portion formed of nuclein, which is the chromatin of [Walther] Flemming. […] The chromatic reticulum of Flemming is only an appearance due to the regular crossing of its convolutions, rarely to their temporary union. 14 December 1887, John Gray M‘Kendrick [i.e., John Gray McKendrick], “IV.—On the Modern Cell Theory, and the Phenomena of Fecundation.”, in Proceedings of the Philosophical Society of Glasgow, volume XIX, Glasgow: Published for the [Philosophical] Society [of Glasgow] by John Smith and Son,[…], published 1888, →OCLC, page 84
   The chromatic threads next arrange themselves in the equatorial plane of the nucleus, and then divide into two groups of threads, each of which forms a daughter nucleus. 1889 September, Harold W[illiam] T[aylor] Wager, “4. Observations on the Structure of the Nuclei in Peronospora, and on Their Behaviour during the Formation of the Oosphere.”, in Report of the Fifty-ninth Meeting of the British Association for the Advancement of Science Held at Newcastle-upon-Tyne in September 1889, London: John Murray,[…], published 1890, →OCLC, section D ([Transactions of the Biology Section]), page 619
   Prof. [Sydney Howard] Vines also attacks my view of the idioplasmatic nature of the nuclear substance (the chromatic grains); and maintains that it is as easy to speak of the continuity of the cell-body as of that of the nuclear substance, and that the one may transmit heritable qualities to progeny as well as the other. 6 February 1890, [August] Weismann, “Prof. Weismann’s Theory of Heredity”, in Nature: A Weekly Illustrated Journal of Science, volume XLI, number 1058, London, New York, N.Y.: Macmillan and Co., →OCLC, page 320, column 2
   If we are amazed at the precision with which the chromatic elements of the nucleus are divided and distributed, we can be no less astonished at the wonderful directive influence exercised by the asters upon the nuclei; […] 1893, E[dwin] G[rant] Conklin, “Second Lecture. The Fertilization of the Ovum.”, in Biological Lectures Delivered at the Marine Biological Laboratory of Wood’s Holl in the Summer Session of 1893, Boston, Mass.: Ginn & Company, published 1894, →OCLC, page 29