Rectangles rhymes with:
triangle's, triangles, angles, bangles, bengals, bojangles', dangles, dingell's, engels, gingles, ingels, ingles, jingles, jungels, jungles, mangels, mangles, mingles, mongols, nightengale's, nightengales, pringle's, shingles, singles, tangles, triangle's, triangles, wrangles