The word is a transparent English compound formed from two ancient nouns. 'Tar' has Germanic origins, traceable to Proto-Indo-European roots related to trees and resin, reflecting its origin as a distilled wood product. 'Paper' has a classical journey from the Greek 'papyros' (the papyrus plant) through Latin and French, evolving to mean any manufactured sheet for writing or wrapping. The compound 'tar-paper' logically combines these elements in the 19th century to name a specific industrial material: paper (the carrier) saturated with tar (the waterproofing agent), directly describing its composition and primary function in roofing and construction.

Structure: tar (substance) + paper (material) - tar: From Old English 'teoru', meaning a dark, viscous liquid. In this compound, it denotes the waterproofing substance. - paper: From Anglo-Norman 'papir', ultimately from Latin 'papyrus', referring to the sheet material. In this compound, it denotes the base material.