phàⁿ-lông-lông冇囊囊

very hollow

very hollow; very spongy; very empty

ideophonic

English Wiktionary, “冇囊囊” (CC BY-SA 4.0) — https://en.wiktionary.org/wiki/%E5%86%87%E5%9B%8A%E5%9B%8A · confidence: Medium (Wiktionary)