Adolescence /ˌæd

the Middle Ages plural noun
a period in European history, between about 1000 AD and 1500 AD, when the power of kings, people of high rank and the Christian Church was strong
millennium /mɪˈlen.i.əm/ noun [ C ] plural millennia or millenniums
a period of 1000 years, or the time when a period of 1000 years ends
The corpse had lain preserved in the soil for almost two millennia.
How did you celebrate the Millennium?
Compare century
period /ˈpɪə.ri.əd/ /ˈpɪr.i-/ noun [ C ] TIME
1. a length of time
Her work means that she spends long periods away from home.
Unemployment in the first half of 1993 was 2% lower than in the same period the year before.
Fifteen people were killed in/over a period of four days.
The study will be carried out over a six-month period.
2. in school, a division of time in the day when a subject is taught
We have six periods of science a week.
3. a fixed time during the life of a person or in history
Most teenagers go through a rebellious period.
The house was built during the Elizabethan period.
phase /feɪz/ noun [ C ]
1. any stage in a series of events or in a process of development
The project is only in the initial phase as yet, but it's looking quite promising.
We're entering a new phase in international relations.
2. a period of strange or difficult behaviour, especially that a young child or person goes through, that will stop after a while
When I was in my early teens I went through a phase of only ever wearing black.
3. The phases of the moon are the regular changes in its shape as it appears to us on Earth.
pioneer /ˌpaɪəˈnɪə r / /-ˈnɪr/ noun [ C ]
1. a person who is one of the first people to do something
one of the pioneers of modern science
a pioneer heart surgeon
2. a person who goes to an area and establishes farms, houses, etc
The pioneers went west across North America, cutting down forests and planting new crops.
timeline /ˈtaɪm.laɪn/ noun [ C ]
1. a line that shows the time and the order in which events have happened
2. a plan which shows how long something will take or when things will happen
ancient /ˈeɪn. t  ʃ ə nt/ adjective
1. of or from a long time ago, having lasted for a very long time
ancient civilizations/rights/laws ancient monuments/ruins/woodlands
the ancient kingdoms of Mexico People have lived in this valley since ancient times .
History, ancient and modern , has taught these people an intense distrust of their neighbours.
2. informal very old
He's got an ancient computer.
3. describes the period in European history from the earliest known societies to the end of the Roman Empire
the ancient Egyptians/Greeks/Romans
The ancient Britons inhabited these parts of England before the Roman invasion.
chronology /krəˈnɒl.ə.dʒi/ /-ˈnɑː.lə-/ noun [ C or U ]
the order in which a series of events happened, or a list or explanation of these events in the order in which they happened
I'm not sure of the chronology of events.
chronological /ˌkrɒn.əˈlɒdʒ.ɪ.k ə l/ /-ˈlɑː.dʒɪ-/ adjective
Give me the dates in chronological order .