atactic, a.
(əˈtæktɪk)
[f. Gr. ἄτακτος not arranged (f. ἀ priv. + τακτός, vbl. adj. f. τάσσ-ειν to arrange) + -ic.]
1. Of language: not syntactic.
| 1842 Chamb. Jrnl. 30 July 218 In this manner syntactic and atactic forms have been respectively formed. |
2. Path. Of or pertaining to or afflicted with ataxia.
| 1880 W. James Feeling of Effort 20 in Anniv. Mem. Boston Soc. Nat. Hist., The special case of the limb being completely anæsthetic, as well as atactic. 1956 Jakobson & Halle Fundamentals of Lang. ii. iv. 74 In one variety of aphasia..sometimes..labeled ‘atactic’, the word is the sole linguistic unity preserved... All other sound-sequences are either alien and inscrutable to him or he merges them into familiar words by disregarding their phonetic aberrations. |
3. Characterized by or exhibiting irregularity in the spatial arrangement of parts in a molecule. Cf. isotactic a., syndyotactic a.
| 1957 Chem. Abstr. 15993 [Abstract of art. by G. Natta et al. in 1957 Gazz. Chim. Ital. LXXXVII]. Stereospecific polymerization... First syntheses of isotactic and atactic polypropene. 1957 Technology July 176/2 The side groups are situated quite at random along the chain; this type of combination is termed ‘atactic’..atactic polypropylene is a rubbery material freezing below -30 deg. C. |