noun
undemocratic
Used as a noun or adjectival noun to describe systems, actions, or attitudes that are not democratic. Often appears in political or social commentary.
その決定は非民主的だと批判された。
The decision was criticized as undemocratic.
反民主 means 'anti-democratic', implying active opposition to democracy, while 非民主 simply means 'not democratic' or lacking democratic qualities.
Formed from the prefix 非 (hi-, 'non-') and 民主 (minshu, 'democracy' or 'democratic'). The prefix 非- is a common Sino-Japanese element for negation, similar to English 'non-' or 'un-'.