すいてき水滴suiteki
1.
A small, rounded quantity of water that forms on a surface or falls from another source, often appearing as a bead of liquid.
2.
A container used for holding water, specifically designed to supply water for a writing tool like a brush or inkstone in traditional Japanese calligraphy.
Example:
気密性でない窓ならば、水滴ができるだろう。