allo-
(ˈæləʊ)
combining form of Gr. ἄλλος other, different, as in allotheism, allochiria, etc. Also in various technical and scientific subjects:
1. Chem. Used to distinguish one of two organic isomers, as allocinnamic, allo-maleic, allo-mucic (acids).
| 1893 Jrnl. Chem. Soc. LXIV. i. 513 Allocinnamic acid. 1894 Ibid. LXVI. i. 173 Allofurfuracrylic Acid and the Formation of Allo-Acids. Ibid., The allo-form of cinnamyl⁓acrylic acid. 1949 S. & L. M. Miall New Dict. Chem. (ed. 2) 21/1 With sterols and related substances the prefix allo- should indicate that rings A and B are in the trans position to each other, but allocholesterol is an exception. |
2. Biol. In comp. with -ploid, as allopolyploid, allotetraploid: having sets of chromosomes derived from different species by hybridization (opp. auto- c).
3. In Philology: see allograph2, allomorph2, allophone.
4. Biol. and Med. Used to refer to genetically dissimilar individuals of the same species.