1.
polka dot; polka dot pattern
A pattern of regularly spaced round dots, commonly used for fabric and design. The most frequent usage in modern Japanese.
Usage
In modern Japanese, 水玉 most commonly refers to polka dot patterns. The full form 水玉模様 (polka dot pattern) is often shortened to just 水玉 when the context is clear. The literal meaning of water droplets is less common but still used poetically.