[f. CONVERGENT: see -ENCE.]
1. The action or fact of converging; movement directed toward or terminating in the same point (called the point of convergence).
1713. Derham, Phys.-Theol., IV. ii. (Seager). The convergences and divergences of the rays.
1794. J. Hutton, Philos. Light, etc., 75. We have here two focal centers … viz. the center of eradiation or emission, and that of convergence or reception.
1848. Macaulay, Hist. Eng., I. 364. In the metropolis of commerce the point of convergence was the Exchange.
1870. R. M. Ferguson, Electr., 29. The convergence in both cases is to a point.
b. ellipt. for degree or point of convergence.
1855. H. Spencer, Princ. Psychol. (1872), I. III. viii. 357. An adjustment of their axes to the requisite convergence.
1885. Manch. Exam., 26 Oct., 5/2. Krakatao is situated at the convergence of three great earth fractures.
2. fig. and transf. Coming or drawing together; concurrence of operations, effects, etc.
1843. Gladstone, Glean., V. iii. 3. From the convergence of such various and unsuspected testimony.
1867. Lewes, Hist. Philos., II. 640. Convergence of effort, not conflict.
1881. Westcott & Hort, Grk. N. T., Introd. § 90. A convergence of phenomena points to some lost reading.
3. Math. Of convergent series or fractions.
1858. Todhunter, Algebra, xl. heading, Convergence and Divergence of Series. Ibid., xl. § 558. Some writers prefer another definition of convergence; namely, they consider a series convergent only when the sum of an indefinitely large number of terms can be made to differ from one fixed value by less than any assigned quantity.
4. Convergent quality, CONVERGENCY. rare.
1833. N. Arnott, Physics (ed. 5), II. I. 208. A lens weaker still might only destroy the divergence of the rays, without being able to give them any convergence.
