IPA: /ɪˈrɪəl/
KK: /ɪˈrɪəl/
Something that is not real or does not exist in reality.
The dream felt so vivid, yet it was completely irreal.
Irreal is formed from "in-" (meaning not) and "real" (from Latin "realis", meaning actual or true). The word "irreal" means not real or lacking reality.
Think of 'not' ('in-') and 'actual' ('real') to remember that 'irreal' refers to something that is not real.