ひとhitoriごとgotoひとりhitoriごとgotoひとりごと一人言hitorigoto
1.

The act of speaking aloud without an audience, often reflecting one's thoughts or feelings in a personal, informal manner.

2.

A verbal expression of one's inner dialogue, typically occurring when one is alone, not intended for others to hear.

3.

A self-directed conversation where an individual articulates their thoughts, sometimes revealing emotions or uncertainties.

Example:

私は彼がぶつぶつ独り言をいうのを聞いた。