Meaning of ONLY in English

(SINGLE OR FEW) [adjective] [before noun; not gradable] - used to show that there is a single one or very few of something, or that there are no othersI was the only person on the train.The only people still working at the factory are the maintenance staff.The only problem with your suggestion is that we haven't enough time to carry it out.Is this really the only way to do it? Are you sure there's no alternative?The only thing I can suggest is that you consult your lawyer about it.The only thing that matters is that the baby is healthy.It was the only thing I could do under the circumstances.Rita was the only person to complain.Chris really is the only person (= the one person who is suitable) for the job.An only child is one who has no sisters or brothers.I was an only child so I got a lot of attention from my parents.As the birth rate falls, increasing numbers of children are only children.

Cambridge English vocab.      Кембриджский английский словарь.