"Densening" is a term used to describe the process of becoming more dense or compact. There are several other terms that can be used as synonyms for "densening", such as "thickening", "compacting", "concentrating", "strengthening", "intensifying", and "firming up". These terms all denote a process of increasing density or compactness, whether it's in physical objects or abstract concepts. Depending on the context, each of these synonyms can be used to convey a slightly different shade of meaning, but they all share the underlying concept of becoming denser or more compact. Whether referring to solids, gases, or even data sets, these synonyms offer a versatile range of language to describe the process of densening.