hyperchromatosis
(ˌhaɪpəkrəʊməˈtəʊsɪs)
[mod.L., f. hyper- 5 + chromato-, chromatin + -osis.]
1. Med. Excessive colouring or pigmentation, esp. of the skin.
| 1886 Syd. Soc. Lex., Hyperchromatosis, Auspitz's term for an excessive deposit of pigment in the epidermis. 1919 Encycl. Medica (ed. 2) VI. 272 Hyperchromatosis, excessive pigmentation, especially in certain skin diseases. |
2. Cytology. [ad. G. hyperchromatose (R. Woltereck 1898, in Zeitschr. f. wiss. Zool. LXIV. 604).] An abnormally large number of chromosomes or amount of chromatin in a cell or nucleus.
| 1898 Jrnl. R. Microsc. Soc. 628 They are remarkable for their excess of chromosomes (hyperchromatosis), and for the tendency these have to group themselves in dyads and tetrads. 1913 J. Ritchie in Pembrey & Ritchie Text-bk. Gen. Path. viii. 240 In malignant tumours the division of the chromosomes between the poles is often unequal... This can be recognized by the existence of differences in size and staining qualities of the nuclei, and the two phenomena are sometimes referred to as hyperchromatosis and hypochromatosis. 1946 Nature 31 Aug. 304/1 A hyperchromatosis and pyknosis of the nucleus which has hitherto been wrongly interpreted as a degeneration. |