N. A short record of something, like a written reminder or a comment. Something that you write down to remind you of something

  • How to take note?
  • Leave a nice note in borrowed items on returning them.
  • Whenever you do business with someone who does a great job, send a note to their boss or supervisor.
  • I took some notes during the lecture.
  • Please note.  
  • Please note that.
  • Please note the difference in the two men.
  • Please note this bill must be paid before the Ninth day of each month.

A “side note” is more like an additional, often minor, comment or piece of information that is separate from the main point. For instance, “In a side note, the author mentioned an interesting fact.”