A folder or box for holding loose papers that are typically arranged in a particular order for easy reference. A line of people or things one behind another. A tool with a roughened surface or surfaces, typically of steel, used for smoothing or shaping a hard material. Place (a document) in a cabinet, box, or folder in a particular order for preservation and easy reference. (of a group of people) walk one behind the other, typically in an orderly and solemn manner. Smooth or shape (something) with a file.