Grwgnachiad, n. a grumbling
Grwgyn, n. broken rumbling
Grwng, n. a grunt; a noise
Grwm, n. a murmur; a growl
Grwn, n. a ridge in a field; a trembling noise
Grwnach, n. a grumbling
Grwnachu, v. to grumble
Grwnan, n. a hum; a purring: v. to hum, to drone
Grwniad, n. a droning
Grwys, n. wild gooseberries