词源 |
incidence n.early 15c., "incidental matter," from Old French incidence (15c.), from Late Latin incidentia, from incidere "to happen, befall" (see incident (n.)). Meaning "act of coming into contact with or affecting" is from 1650s. In physics, of rays of light, etc., considered with reference to direction, from 1620s. updated on December 07, 2020 |