Synonyms and related words :
Attic, aesthetic, artistic, back-door, backstairs, chaste, choice, clandestine, classic, covert, excellent, feline, furtive, hidlings, hole-and-corner, hugger-mugger, humble, in good taste, meek, modest, of choice, of quality, pleasing, privy, pure, quiet, restrained, shifty, simple, skulking, slinking, slinky, sly, sneaking, sneaky, stealthy, subdued, surreptitious, tasteful, tasty, unaffected, unambitious, unaspiring, unassuming, unboastful, under-the-counter, under-the-table, undercover, underground, underhand, underhanded, understated, unimposing, unostentatious, unpresuming, unpresumptuous, unpretending, unpretentious, well-chosen