In English morphological literature, the term 'tautological compound' has been typically used to refer to two distinct -but closely related -phenomena: (1) compounds composed of a hyponym and a superordinate term (such as oak tree); and/or (2) compounds based upon two synonymous units (such as subject matter). Such combinations are one of the quirkiest -and least researched -phenomena of English compounding. Their oddity can be attributed to two main factors. First, as their name, 'tautological compound' implies, at face value such combinations can be considered as prime examples of the redundancy of language. Second, they do not follow normal compound-forming rules in the sense that both constituents can function as the semantic head (as opposed to 'normal' English compounds, which follow the Right-Hand Head Rule).Perhaps it is the quirkiness of tautological compounds that accounts for the fact that not much has been said about them in traditional accounts of compounding, which typically relegate them to a marginal area of the English language. However, there is more to tautological compounds than meets the eye. What the present study wishes to demonstrate is that the term 'tautological compound' is a misnomer, as such combinations are far from being tautological or redundant in their meaning. Accordingly, the article first clarifies the notion of tautological compound, and then aims to give an account of the various roles that such combinations play in language, thereby demonstrating their non-tautological and non-redundant nature -in order to assign this much-neglected category to its proper, well-deserved place within English word formation.