Is there any difference in usage between inconclusive and non-conclusive (nonconclusive)? Inconclusive is more popular in research compared to non-conclusive, using pubmed search, 20,872 and 260 … Except non is not an english word, it is a prefix of latin origin.

British rules differ, and … To record and summarize the discussion in the comments, while the oed mostly uses the hyphen, many other dictionaries don't, and the ngrams show higher non-hyphenated usage than hyphenated.