bubble nucleus
Technical term in physics and engineering for the initial microscopic cavity or seed from which a bubble forms in a liquid, often in cavitation or boiling contexts.
Cavitation occurs when bubble nuclei in a liquid grow.
In ultrasonic cleaning, the oscillation of bubble nuclei removes dirt.
Compound of 気泡 (bubble) and 核 (nucleus). The exact historical derivation is uncertain, but the term follows standard scientific naming conventions.