noun
grumbling talk; tedious complaints; continual moaning
Refers to a conversation or story that consists mainly of complaints or grumbling, often perceived as tiresome.
彼の愚痴話にはもううんざりだ。
I'm fed up with his tedious complaints.
飲み会が愚痴話ばかりでつまらなかった。
The drinking party was boring because it was nothing but grumbling.
Compound of 愚痴 (grumbling, complaint) and 話 (talk, story). The exact historical derivation is uncertain, but the word is a straightforward modern compound.