Crossword Dictionary
lackluster
lackluster, lacklustre, lusterless, lustreless - a
lacking brilliance or vitality; "a dull lackluster life"; "a lusterless performance"
lacking luster or shine; "staring with lackluster eyes"; "lusterless hair"
Lackluster is a compound adjective that means what it sounds like: if something is lackluster it lacks luster; in other words, it is without brilliance, shine, or vitality. Think dull.
Shakespeare gave us the compound lackluster, first using the term in his play As You Like It. In 2:7, the character Jacques says, "And then he drew a dial from his poke, And, looking on it with lack-lustre eye..." Since Shakespeare first coined this word, it has been used to describe anything "blah"; lackluster sales would worry shop owners and a lackluster prom dress might help you blend in with the wallpaper.
etymology
also lack-luster, c. 1600, "dull, wanting brightness" (originally of eyes), first attested in "As You Like It," from lack (v.) + luster (n.1). Such combinations with lack- were frequent once: Shakespeare alone also has lack-love, lack-beard, lack-brain, lack-linen. Outside Shakespeare there was lackland (1590s), of a landless man; lack-Latin (1530s), of an ignorant priest; lack-learning (1590s), lack-wit(Dryden), lack-thought (1829), lack-life (1889), and the comprehensive lack-all (1850).