Drab rhymes with:
crab, crabb, crabbe, grab, grabbe, krabbe, prab, rab, rabb, ab, bab, babb, cab, colab, crab, crabb, crabbe, dab, fab, flab, gab, glab, grab, grabbe, jab, knab, knabb, krabbe, lab, labbe, mab, macnab, mcnab, mcnabb, nab, nabb, prab, prefab, rab, rabb, sabb, scab, schab, slab, stab, tab, tabb
Drab sounds like:
darby, darpa, dauterive, deharbe, derby, derive, diatribe, dorf, dorff, drape, drapeau, dravo, drip, drive, drive-by, driveway, droop, droopy, drop, drop-off, dropoff, drove, drub, drupe, durfee, durfey, dwarf