unobtrusive

un- +‎ obtrusive

unobtrusive (comparative more unobtrusive, superlative most unobtrusive)

1. Not noticeable or blatant; inconspicuous.
   • 1925, F[rancis] Scott Fitzgerald, chapter I, in The Great Gatsby, New York, N.Y.: Charles Scribner’s Sons, OCLC 884653065; republished New York, N.Y.: Charles Scribner’s Sons, 1953, →ISBN:

     Sometimes she and Miss Baker talked at once, unobtrusively and with a bantering inconsequence that was never quite chatter, that was as cool as their white dresses and their impersonal eyes in the absence of all desire.