countable/uncountable the number of years that someone has livedIt was difficult to guess his age.
The average age of the delegates was over 60.
children under the age of seven
reach the age of: She’ll only inherit when she reaches the age of 18.
at/from the age of: At the age of 10, I went to live with my aunt.
at/from an early age (=a young age): The sisters have been playing music together from an early age.
at your/his/her etc age (=because of how young or old someone is): At her age, she might be expected to take things easy.
of all/different ages: The film is designed to appeal to people of all ages.
difference in age: Her parents disapproved of the relationship because of the difference in age.
years of age: He started work there at 14 years of age.