: a long, thin piece of cotton, silk, etc., used for sewing
: a long, thin line of something
: the raised line that winds around a screw
: to put a thread, string, rope, etc., through a hole in something
: to put (film or tape) into a movie camera, tape recorder, etc., so that it is ready to be used
: to move forward by turning and going through narrow spaces
What made you want to look up thread? Please tell us where you read or heard it (including the quote, if possible).