Tasteful comes from taste + -ful. Taste is from Old French taster ('to taste, feel, touch'), from Vulgar Latin *tastare, perhaps a blend of Latin taxare ('to handle') and gustare ('to taste'). The historical chain includes Old French taster and Latin taxare. The quoted older senses, "to taste, feel, touch", "to handle", and "to taste", supply the semantic anchors for tasteful. The formation is best read as suffixal and borrowed: the word tasteful carries its older form-history into a compact English lexical shape. In present English it is used as a adj, "showing good aesthetic judgment or discretion". English derivatives include tastefully and tastefulness; related English forms include taste, tasteless, and distaste. The result is a adj whose etymology preserves both the older form and the later English specialization.