Firstier rhymes with:
bustier, bustier, isautier, metier, montier, poitier, ratier, behavior, belier, bonier, bowyer, bustier, clothier, collier, configure, conyer, corbusier, devillier, disfigure, duvalier, elsevier, espalier, failure, familiar, figure, flavier, foncier, frashier, gonyer, grolier, havier, hellier, hotelier, insecure, isautier, jr, juicier, junior, kuzniar, lawyer, lockyer, manicure, megacarrier, metier, misbehavior, monsignor, montagnier, montier, msgr, navellier, nicollier, papier, peculiar, pedicure, pizzazier, poitier, ratier, reconfigure, roshier, savier, savior, sawyer, schwalier, scohier, sellier, senior, sevier, spanier, sr, tenure, trendier, unfamiliar, walkure, xavier, yearearlier
Firstier sounds like:
fabricator, firstar, foerster, forecaster, forester, forestry, forister, forrester, forster, fracture, freighter, freshwater, fruchter