喃 (nán) — (used in 喃喃) to murmur, to mutter

Definition

喃 is a bound form — it never stands alone; it only appears in the reduplicated 喃喃, meaning to murmur or mutter softly to oneself.

bound form

(used in 喃喃) to murmurto mutter

，。
Tā dī shēng nán nán le yí jù, méi rén tīng qīng.
He muttered a sentence in a low voice, and no one heard it clearly.
，。
Tā zuò zài chuāng qián, zuǐ lǐ bù tíng dì nán nán zhe.
She sat by the window, mumbling continuously under her breath.
，。
Lǎo rén nán nán le jǐ shēng, yòu chén mò le.
The old man muttered a few times and then fell silent again.