Held fast is a phrase that means to be firmly gripped or tightly held onto. Synonyms for this phrase include, but are not limited to: clutched, grasped, secured, anchored, clinched, clasped, embraced, hugged, and clung onto. These synonyms all imply a sense of steadfastness and resilience in holding onto something. Whether it is a physical object, an idea, a belief, or a relationship, these synonyms indicate a strong commitment and determination to keep it close. The use of these synonyms can add depth and variety to writing while conveying a similar sense of holding on with a firm grip.