also: ほうまつ · うたがた
Refers to a bubble on the surface of a liquid. The reading うたかた is literary/poetic; ほうまつ is technical.
Bubbles are floating on the water's surface.
The soap bubbles disappeared quickly.
泡沫 is a literary word for foam or bubbles, often used metaphorically for something fleeting, whereas 泡 is the plain, concrete term.
Standard kanji spelling for the reading うたかた; also read ほうまつ in technical contexts.
Technical or formal reading for 'bubble'; rarely used for the ephemeral sense.
Kana spelling is common in literary and poetic usage, and avoids confusion with the ほうまつ reading.
Archaic or dialectal variant of うたかた; not commonly used in modern standard Japanese.
The reading うたかた is of uncertain origin, possibly from うた (song) + かた (shape), but this is speculative. The kanji 泡沫 literally mean 'bubble' and 'foam', and the reading ほうまつ is the on'yomi.