wishful thinkingnoun [ U ]
uk/ˌwɪʃ.fəl ˈθɪŋ.kɪŋ/us/ˌwɪʃ.fəl ˈθɪŋ.kɪŋ/the imagining or discussion of a very unlikely future event or situation as if it were possible and might one day happen:
"Do you think you might be in line for promotion?" "No, it's just wishful thinking."