I'LL EAT MY HAT
Meaning of I'LL EAT MY HAT in English
( informal ) used to say that you think sth is very unlikely to happen :
If she's here on time, I'll eat my hat!
Oxford Advanced Learner's English Dictionary.
Оксфордский английский словарь для изучающик язык на продвинутом уровне.
2005