Undercoat rhymes with:
overcoat, callicoat, chilcoat, chilcote, fivecoat, hathcoat, jefcoat, liddicoat, malicoat, overcoat, petticoat, raincoat, redcoat, turncoat, wescoat
Undercoat sounds like:
unaddressed, unauthorized, undercooked, undercut, underside, undersized, understate, understated, understood, understudy, underused, underweight, underweighted, undressed, uninterested