a train of thought

train of thought

One's uninterrupted progression of thinking. When the phone rang, it derailed my train of thought—I totally forget what I was talking about! Please don't interrupt my train of thought when I'm writing.
See also: of, thought, train
Farlex Dictionary of Idioms.

a train of ˈthought

the connected series of thoughts that are in your head at a particular time: The phone ringing interrupted my train of thought.
See also: of, thought, train
Farlex Partner Idioms Dictionary
See also:
  • train of thought
  • lose (one's) train of thought
  • lose train of thought
  • (one's) day in court
  • (from) top to toe
  • (there's) no peace/rest for the wicked
  • (one's) old man
  • (one's) old lady
  • (one's) jig is up
  • ring with