Definition of "unfrequently"

She not unfrequently stopped at the Parsonage, and had a few minutes' conversation with Charlotte, but was scarcely ever prevailed upon to get out.

1813 January 27, [Jane Austen], chapter 30, in Pride and Prejudice: […], volume I, London: […] [George Sidney] for T[homas] Egerton, […]

Near to the jail, and by consequence near to Smithfield also, and the Compter, and the bustle and noise of the city; and just on that particular part of Snow Hill where omnibus horses going eastward seriously think of falling down on purpose, and where horses in hackney cabriolets going westward not unfrequently fall by accident, is the coach-yard of the Saracen's Head Inn;

1838 March – 1839 October, Charles Dickens, chapter 4, in The Life and Adventures of Nicholas Nickleby, London: Chapman and Hall, […], published 1839

Hurry had all the prejudices and antipathies of a white hunter, who generally regards the Indian as a sort of natural competitor, and not unfrequently as a natural enemy.

1841, James Fenimore Cooper, “chapter 3”, in The Deerslayer

Kings and free states not unfrequently maintained a troupe of professional singers and dancers, ready to undertake at the shortest notice the performance of the most elaborate Ode.

1879, F. D. Morice, Pindar, chapter 2, pp. 12-13