cupule

Any small structure shaped like a cup, such as at the base of an acorn, or the sucker on the feet of some flies.

Japanese Meaning

杯形の構造体、つまり小さなカップのような形状を持つ部分 / 植物学的には、どんぐりの基部に見られる杯状の部分 / 昆虫学的には、一部のハエの足に見られる吸盤状または杯状の構造

The botanist carefully examined the acorn's cupule to determine the oak species.

植物学者はどんぐりの殻斗を注意深く調べて、どのブナ科の種かを判断した。

Sense（1）

Any small structure shaped like a cup, such as at the base of an acorn, or the sucker on the feet of some flies.

Then they extract a three-angled beechnut from its cupule, weigh it, and push it into the loam.

cupules

（ plural ）