Family name origins & meanings
- Polish and Jewish (from Poland) : from Polish kaczor ‘drake’, applied either as a nickname or (especially among Jews) as an ornamental name.
- Hungarian : nickname from Slovak kocúr ‘tom cat’; alternatively it may be from Hungarian kacor ‘curved knife’ (from Southern Slav koser, kosir, kosor), perhaps as a metonymic occupational name for a maker or user of such knives.