equationaladj.

1864 W. Hipsley (title) Equational Arithmetic: Questions of Interest, Annuities, &c.

1880 Athenæum 13 Nov. 636/3 A further theoretical aid in equational logic.

1875 E. H. Knight Amer. Mech. Dict. II. 807/2 Equational box, invented by Houldsworth. A differential gearing used in the bobbin and fly machine for the adjustment of different degrees of twist, for different yarns.

1920 W. E. Agar Cytol. 50 Now in a meiosis with tetrad formation of the Copepod type it follows that if both the joints represent division planes, one division must be longitudinal (or equational, since the resulting daughter chromosomes receive similar sets of chromatin elements), and the other division must be transverse (or reductional, since each resulting daughter chromosome receives only one half of the set of chromatin elements).

1949 C. D. Darlington & K. Mather Elements of Genetics ii. 52 The distribution of the chiasmata in the pairing segment relative to the centromere and the differential segments then decides whether the first division is reductional for these segments or equational.

1933 L. Bloomfield Lang. xi. 173 The equational type [of sentence] was less common [in Latin] than in Russian: beātus ille ‘happy (is) he’.

1961 R. B. Long Sentence & its Parts v. 115 The common-voice forms of be are reversible when be is a true equational verb. The worst thing is the lights.

1964 Language 40 272 ‘Equational sentence’ is a good term for a sentence containing a copula.

1964 R. H. Robins Gen. Linguistics vi. 234 In some languages a favourite, productive, sentence type is found beside those containing a verb, namely a noun + noun or a noun + adjective structure, with no verb required to complete it. This type, which is sometimes labelled equational, is found in Russian.

1881 W. S. Jevons in Nature 24 Mar. 487/2 They [sc. secondary propositions] obey exactly the same formal laws as primary propositions, and are of course expressed equationally.