Singra

As defined by the Cleasby & Vigfusson Old Norse to English dictionary:

singra

að, to hum a song or ditty.

Possible runic inscription in Younger Futhark:ᛋᛁᚾᚴᚱᛅ
Younger Futhark runes were used from 8th to 12th centuries in Scandinavia and their overseas settlements