Flattener is a word that refers to something that makes flat or reduces unevenness. Synonyms for this term include words such as leveler, smoother, straightener, and evenizer. These words all suggest an action or tool that brings something to a more even surface or position. Other synonyms for flattener may include words such as compressor, presser, or squeezer, which suggest a method of physically flattening or compacting something. Additionally, the word can be used in a figurative sense, such as in the context of flattening hierarchies or eliminating barriers, in which case synonyms might include words such as equalizer, democratizer or unifier.