Flageolet rhymes with:
collette, mallette, nicolet, nicolette, veillette, arlette, berlet, boulet, boulette, bramlette, brouillet, brouillette, chelette, colette, collette, ellette, flett, follette, furlett, gelette, gillette, goulet, goulette, guillet, guillette, gullette, hulette, inglett, jolette, klett, laviolette, let, lett, maillet, mallette, marlette, millette, nellette, nicolet, nicolette, nolette, parlette, paulette, plett, quellette, rillette, rolette, rollet, roulette, rowlette, umphlett, vallette, veillette, villette, violette, willette