( informal ) used before mentioning a worry or problem you have with sth :
I'd love to come—the only thing is I might be late.
( informal ) used before mentioning a worry or problem you have with sth :
I'd love to come—the only thing is I might be late.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005