The terms customs uses are completely unrelated to normal human words for things. They have a 21-page document (https://www.cbp.gov/sites/default/files/assets/

The terms customs uses are completely unrelated to normal human words for things. They have a 21-page document (https://www.cbp.gov/sites/default/files/assets/documents/2020-Feb/icp013_3.pdf https://www.cbp.gov/sites/default/files/assets/documents/202...) describing the difference between a bolt and a screw. It starts off by citing the regulation differentiating them by intended use, then spends the rest of the document differentiating them solely by looks.