1828–32 N. Webster Amer. Dict. Eng. Lang. Viable, capable of living, as a new~born infant or premature child.

1859 Todd's Cycl. Anat. & Physiol. V. 200/1 The delivery of a fœtus of viable or full-grown size.

1881 Trans. Obstetr. Soc. 22 276 Such narrowing or deformity of the female pelvis..as will absolutely preclude the birth of a viable child.

1885 G. L. Goodale in A. Gray & G. L. Goodale Bot. Text-bk. (ed. 6) II. ii. xiv. 446 Polyembryony, [is] the production of two or more viable embryos in a seed.

a1894 R. L. Stevenson In South Seas (1896) i. iv. 28 To judge by the eye, there is no race more viable; and yet death reaps them with both hands.

1927 H. Peake & H. J. Fleure Apes & Men 31 (note) Viable, a term meaning ‘capable of maintaining its life or the life of its kind’, is used here in preference to the much controverted word ‘fit’.

1848 Tait's Edinb. Mag. 15 702 The rest are waiting for the proper medium, the viable medium, the medium of harmony.

1883 G. P. Lathrop Hawthorne's Wks. XI. 435 What we have here is a romance in embryo; one, moreover, that never attained to a viable stature and constitution.

1955 Sc. Jrnl. Theol. 8 93 A viable faith in the twentieth century must be able to take into itself a certain scepticism and relativism with regard to all rational systems.

1958 ‘A. Burgess’ Enemy in Blanket xv. 174 It was time he..planted the seeds of a viable relationship between his wife and himself.

1958 Economist 8 Nov. 485/2 The plans must..be such as to make the farm ‘viable or more viable’—i.e. capable..of yielding its occupier at least the income of a skilled agricultural worker.

1962 Listener 5 Apr. 605/2 The Russian nuclear capacity appears..to be..not capable of destroying anything like enough of the American potential for a Russian first strike to be a viable proposition.

1962 P. Gradon in Davis & Wrenn Eng. & Medieval Stud. 66 This simple explanation..is not viable for another group of texts to which I now wish to turn.

1971 H. Macmillan Riding Storm iv. 146 It [sc. Jordon] was not in economic terms a viable state without British support.

1977 M. Wiles in J. Hick Myth of God Incarnate i. 3 They do not of themselves prove that the concept of a ‘Christianity without incarnation’ is a viable concept.