na-adjective, noun
viscous; thick and sticky
Describes liquids or semi-liquids that are thick, sticky, and flow slowly. Often used in technical or formal contexts.
この液体は粘稠で、なかなか流れない。
This liquid is viscous and doesn't flow easily.
粘稠な分泌物が傷口を覆っていた。
A thick, sticky secretion covered the wound.
Compound of 粘 (sticky) and 稠 (dense, thick). The exact historical derivation is uncertain, but the combination conveys the idea of thick, sticky consistency.