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general::
Phrase(s): (I’m) (just) thinking out loud.
Fig. I’m saying things that might better remain as private thoughts. (A way of characterizing or introducing one’s opinions or thoughts. Also past tense.) • Sue: What are you saying, anyway? Sounds like you’re scolding someone. Bob: Oh, sorry. I was just thinking out loud. • Bob: Now, this goes over here. Bill: You want me to move that? Bob: Oh, no. Just thinking out loud.
McGrawhill's American Idioms And Phrasal Verbs