periodicityn.

1820 J. F. W. Herschel in Philos. Trans. (Royal Soc.) 110 65 The number of periods performed depends..3rdly, on..the thickness of the plate, and whatever other cause or limit of periodicity may happen to prevail.

1852 E. Greswell Fasti Temporis Catholici I. 20 Might we be permitted to invent a word, which..would be the best adapted to express this particular property of time,..it would be some such term as Periodicity.

1882 S. H. Vines tr. J. von Sachs Text-bk. Bot. (ed. 2) 755 A similar periodicity exists in the growth of leaves when day and night alternate normally.

1932 S. Zuckerman Social Life Monkeys & Apes iii. 32 Sexual periodicity is even more conspicuous in the lower mammal than in man.

1973 Computers & Humanities 7 191 Periodicity (or rhythm) on all levels is an important characteristic of most Western music.

1991 Saudi Med. Jrnl. 12 144/2 Chronic idiopathic neutropenia is also not asymptomatic and shows periodicity but not with the mathematical regularity of cyclic neutropenia.

1848 W. T. Smith (title) The periodoscope, with its application to obstetric calculations and the periodicities of the sex.

1875 N. Amer. Rev. 120 187 In this harsh climate..in their case, periodicity, nervous system, intellect, and health require especial care.

1879 H. E. Roscoe & C. Schorlemmer Treat. Chem. II. ii. 506 The law of periodicity was afterwards further developed by Meyer and Mendelejeff.

1907 Westm. Gaz. 4 Feb. 6/3 Gallium, scandium, and germanium, all subsequently discovered, did fit into the scale of ‘periodicity’.

1969 A. J. Ihde in J. W. Van Spronsen Periodic Syst. Chem. Elem. p. x The periodic table reached its final forms before atomic structure revealed the basis for periodicity.

1996 Science 22 Mar. 1692/3 The periodic table itself [was] devised over the centuries from the observed periodicity in properties of the chemical elements at a pressure of 1 atm.

1900 Jrnl. Soc. Arts 48 848/2 The other carrying about 20 amperes with a periodicity of 60 cycles per second.

1913 Chambers's Jrnl. Jan. 102/1 The electricity used for wireless telegraphy is..used under different conditions as to pressure and periodicity.

1938 Times 13 Oct. 8/3 The periodicities of the front and back springs are arranged at a predetermined variance so that coincidence should not occur.

1943 Gloss. Terms Electr. Engin. (B.S.I.) 11 Frequency (periodicity, deprecated), the number of cycles per second. The reciprocal of the period.

1979 PN Rev. No. 10. 2/1 I have wanted since 1977 to increase the periodicity of the magazine to six-times yearly.

1984 E. P. DeGarmo et al. Materials & Processes in Manuf. (ed. 6) xviii. 514 Recent research has shown that the periodicity or spacing of the shear fronts remains constant in a material regardless of the cutting speed.

2001 J. Greenlaw Longcase Clocks 8 The escapement rotates one tooth at a time, but the speed is dictated by the periodicity of the pendulum, a function of its length.