MHB, MHb, or mhb can refer to:
== Biology and medicine == Mycorrhiza helper bacteria, a group of bacteria that have a symbiotic relationship with both fungi and plants Midbrain−hindbrain boundary, a region in the developing brain that helps separate the midbrain from the hindbrain Medial habenula, a brain region in the middle of the habenula Mueller-Hinton broth, similar to Mueller-Hinton agar, a growth medium that can be used for the virtual colony count technique
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).