氾

A phono-semantic compound composed of:

水 — semantic component meaning “water”; 㔾 — phonetic component indicating the sound (범 / fàn). The character originally described water overflowing or spreading outward.
Semantic development: - water overflowing its banks; - flooding; - spreading widely or excessively.

The compound 범람 (氾濫) is commonly used for rivers overflowing or something spreading excessively.
범람 (氾濫) — flooding; overflow 범월 (氾越) — transgression; overstepping limits

氾 often appears in contexts describing flooding or uncontrolled spreading (e.g., information, rumors, or emotions).
Related characters: 泛 — to float; spread widely 洪 — flood

溢 — overflow

These characters relate to water overflowing or spreading.