noun
a layer of wood, shell or bone developed in one year, or in another regular period of growth, that an expert can look at to find out how old sth is
noun
a layer of wood, shell or bone developed in one year, or in another regular period of growth, that an expert can look at to find out how old sth is
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005