Herb's rhymes with:
blurbs, curbs, disturbs, erbes, herbs, kerbs, perturbs, serb's, serbs, serbs', verbs, zirbes
Herb's sounds like:
harbach, harbaugh, harbeck, harbuck, harps, harvey's, herbaceous, herbeck, herbig, herbs, herpes, hirabayashi, horrific, horvac, horvac's, hrabak, hrubik