IPA: /ˌhaɪpərˈmjuːtəˌbɪləti/
KK: /haɪpərˈmjuːtəˌbɪləti/
The condition of changing or mutating very quickly and frequently.
The hypermutability of the virus makes it difficult to create an effective vaccine.
Hypermutability is formed from "hyper-" (meaning over or excessive) and "mutabilitas" (from Latin "mutabilis", meaning changeable). The word describes the quality of being excessively changeable or subject to rapid changes.
Think of 'hyper-' meaning excessive and 'mutability' relating to change — this helps you remember that hypermutability refers to an excessive ability to change.