There are a few words in English that end with -omb.

Let’s talk specifically about these three:

• Bomb /bɑm/
• Comb /koʊm/
• Tomb /tum/

Surprisingly (or perhaps not, if you’re used to English quirks), all three are pronounced very differently. As you can see from the IPA transcriptions above, the only feature these words share is that the final b is silent.

So, to answer the question in the title – how to pronounce comb – it rhymes with foam, and does not rhyme with bomb.

Audio on Forvo:

Honeycomb photo by Ante Hamersmit on Unsplash