Source : Webster's Revised Unabridged Dictionary (1913)

Single-breasted \Sin"gle-breast`ed\, a.
   Lapping over the breast only far enough to permit of
   buttoning, and having buttons on one edge only; as, a
   single-breasted coast.

Source : WordNet®

single-breasted
     adj : (of clothing) closing with a narrow overlap and fastened
           with a single row of buttons; "a single-breasted
           jacket" [ant: {double-breasted}]