1.
idle talk; chitchat; pointless chatter
Conversation that serves no productive purpose. Can be mildly negative (wasting time) or neutral (casual socializing), depending on context.
Usage
無駄話 implies the conversation has no particular point or purpose. In work settings it is negative (time-wasting), but socially it can be neutral or even positive (enjoying casual conversation).
Common collocations
Forms
無駄 (futile, pointless) + 話 (talk). The は becomes ば through rendaku.
Similar words
雑談 (casual conversation) is more neutral and common. おしゃべり (chatting) is lighthearted. 無駄話 specifically emphasizes the lack of purpose.