pre-printing; printing one color before others
Technical printing term: applying one specific ink color before the rest in a multi-color process.
For this poster, we pre-print the black ink first, then overlay the other colors.
Compound of 先 (saki, 'before') and 刷り (zuri, 'printing'). The exact historical derivation is uncertain, but the term is conventionally associated with pre-printing in multi-color processes.