1900 E. R. Henry i. 47 These abrupt beginnings and endings, islands, bifurcations, etc., are known as ridge characteristics.
1954 F. Cherrill vii. 75 The incriminating impressions of the ridge characteristics of a fragment of his palm.
2002 19 July 340/2 There is a vanishingly small statistical likelihood that some set of ridge characteristics..on a given fingerprint will be found in a random sample of the population.