1866 W. King & T. H. Rowney in Q. Jrnl. Geol. Soc. 22 i. 187 All these varieties are considered to belong to one axial system—the monoclinate; but being obviously of other forms than one, and as they are all chemically alike, we propose to call them allomorphs.

1882 Jrnl. Royal Microsc. Soc. 2 360 It is frequently due to the peculiarities of a layer of flocculite (a nonfibrous allomorph of serpentine).

1949 Jrnl. Amer. Chem. Soc. 71 4139/2 We consider the two forms allomorphs of Prelog's cis-form, since we were able to derive each from the other one.

1963 Science 11 Oct. 232/2 Nearly all the bivalve mollusks have shells composed of conchiolin and aragonite, the orthorhombic allomorph of calcium carbonate.

2004 Polymer 45 4541/1 Elucidation of the crystal structures of cellulose allomorphs is one of the most difficult problems remaining in cellulose science.

1945 P. L. Garvin in Language 21 253 The oblique stem of this suffix is /benn/, which differs from the front allomorph of the suffix..only by the reduplication of the final consonant.

1951 G. L. Trager & H. L. Smith Outl. Eng. Struct. ii. 60 Suffixes, especially inflectional ones, usually have many allomorphs.

1962 E. F. Haden et al. Resonance-theory for Ling. iii. 30 The forms..showed,..handed,..are..analyzable into stem + suffix:../ʃow/ + /d/, /hænd/ + /id/... Each of these endings signals the same grammatical meaning, namely, ‘past’, and they can all be classed together in the morpheme {-D} (or {past})... The several allomorphs of this morpheme ({M₁}) are statable as sets of phonemes, but more accurately as sets of allophones.

2000 S. Franks & T. H. King Handbk. Slavic Clitics 35 The nonsyllabic preposition v ‘in’ has a special allomorph va before bound pronouns.