The word 'towline' is a transparent compound formed from two Old English roots. The first element, 'tow', originates from the Germanic verb meaning to drag or pull, a concept central to the word's function. The second element, 'line', descends from the Latin līnea, via Old English, referring specifically to a cord or rope. When combined, these morphemes create a logical and literal descriptor for a rope designed for the explicit purpose of pulling another vessel or object, perfectly capturing the tool's utility in maritime and terrestrial contexts.

Structure: tow (to pull) + line (rope) - tow: From Old English togian (to drag, pull), of Germanic origin. Functional role: Verb root indicating the action. - line: From Old English līne (rope, series), from Latin līnea (linen thread, string). Functional role: Noun root indicating the object.