Unvarnished comes from un- ('not') plus varnished, from varnish, from Old French vernis, from Medieval Latin veronix ('sandarac resin'), possibly from Late Greek beronikē. The historical chain includes Old English un- and Old French vernis. The quoted older senses, "not" and "sandarac resin", supply the semantic anchors for unvarnished. The formation is best read as borrowed: the word unvarnished carries its older form-history into a compact English lexical shape. In present English it is used as a adj, "plain and direct, without embellishment; not coated with varnish". Related English forms include varnish. The result is a adj whose etymology preserves both the older form and the later English specialization.