What is the meaning of Kayser?

A unit of wavenumber in the CGS system of units, equivalent to the number of waves in one centimeter.

An emperor (the ruler of an empire; a supreme ruler)

↑ “cāsere, n.”, in MED Online, Ann Arbor, Mich.: University of Michigan, 2007.

↑ Dance, Richard (2003), Words derived from Old Norse in early Middle English: studies in the vocabulary of the South-West Midland texts (Medieval and Renaissance Texts and Studies; 246)‎, Part B, Tempe, Arizona: Arizona Center for Medieval and Renaissance Studies, →ISBN, →OCLC, § 3.1, pages 427-429.

↑ Björkman, Erik (1900), “Chapter I. Phonetic criteria of Scandinavian loan-words in English”, in Scandinavian loan-words in Middle English (Studien zur Englischen Philologie; 7)‎, Part I, Halle A.S.: Max Niemeyer, pages 56-57.

Caesar, title of Roman and Byzantine emperors

Kaiser (emperor of a German-speaking country)

Source: wiktionary.org