coolsaet (Middle Dutch) comes from Dutch zaad, from Dutch plant, from Middle Dutch plante, from Latin planta, from Proto-Italic plāntā, from Proto-Indo-European pléh₂-n̥t-eh₂, from Proto-Indo-European pleh₂- — flat.
Ancestry of “coolsaet”, step by step
coolsaet traces back through two separate lines of ancestry.