FromProto-Vietic*k-rɔh(“to bark”). CompareProto-Katuic*kroh (whencePacohcrouh) andProto-Palaungic*-rɔːh.
The word might be originallyonomatopoeic, although it is no longer so in its modern form.
The similar-lookingMandarin說/说 (shuō), which means "to speak", is afalse cognate.