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What Do “AD” and “BC” Mean? Definitions and Examples

Updated on August 14, 2023Students
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If you’ve ever wondered what the letters AD and BC mean or sometimes have trouble writing dates correctly, you’ve come to the right place. This article is a complete resource for people searching for information on AD and BC and provides a guide for using them in writing.

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What are AD and BC?

AD stands for Anno Domini, which is Latin for in the year of the Lord. It’s a way of counting years based on the estimated birth of Jesus Christ. BC stands for Before Christ, and it’s a way of counting years before the estimated birth of Jesus Christ. AD starts with year 1 and continues to the present day. BC starts with the year before Christ’s birth, 1 BC, and counts backward to the year 10,000 BC.

The use of AD and BC dates back to the sixth century, and they were introduced by a monk named Dionysius Exiguus. He wanted to create a system of dating based on the birth of Jesus Christ. Today, AD and BC are used to label the years on the Gregorian calendar, which is the most widely used calendar in the world. The Gregorian calendar is a solar calendar that Pope Gregory XIII introduced in 1582.

AD and BC provide a useful framework for historical and religious contexts; however, they’re not completely accurate. The accuracy of AD and BC is limited by the fact that they’re based on an approximation of the birth of Jesus Christ, which is itself not entirely certain. In addition, there are inconsistencies and errors in the historical records that make it difficult to determine exact dates for many events. Despite these limitations, AD and BC remain the most common way of dating historical events and are widely recognized and accepted around the world.

When should you use AD and BC?

Use AD and BC when referring to dates based on the Gregorian calendar. They are commonly used in academic writing, historical documents, and religious texts.

AD should be used when referring to years after the birth of Jesus Christ, beginning with year 1 and continuing to the present, while BC should be used when referring to years before the birth of Jesus Christ, 1 BC to 10,000 BC.

AD and BC vs. CE and BCE, and other forms of dating

In science, the terms AD and BC are not commonly used. Instead, scientists often use other dating systems. For example, in geology, scientists use the term BP, which stands for before present. BP is based on the carbon-14 dating method and refers to the number of years before the present that an object or event occurred.

In astronomy, scientists use the terms CE and BCE, which stand for Common Era and Before Common Era, respectively. CE and BCE are used to date astronomical events, such as eclipses and planetary conjunctions. CE and BCE are becoming more common in academic writing and are used to avoid religious connotations.

Overall, while AD and BC remain the most widely used systems of dating in historical and religious contexts, scientists use more precise dating methods that are better suited to the needs of their respective fields.

AD and BC examples

Here are examples of AD in a sentence:

  • The Great Wall of China was completed in the 17th century AD.
  • William Shakespeare was born in 1564 AD.
  • The American Revolutionary War began in 1775 AD.
  • The first iPhone was released in 2007 AD.
  • The COVID-19 pandemic began in 2019 AD.

Here are examples of BC in a sentence:

  • The ancient Egyptians built the pyramids around 2500 BC.
  • Julius Caesar was assassinated in 44 BC.
  • The Roman Republic was founded in 509 BC.
  • The Great Wall of China was started in the 7th century BC.
  • The first Olympic Games were held in 776 BC.

AD and BC FAQs

What do AD and BC mean?

AD stands for Anno Domini, which is Latin for in the year of the Lord. It’s a way of counting years based on the estimated birth of Jesus Christ. BC stands for Before Christ, and it’s a way of counting years before the estimated birth of Jesus Christ.

How do they relate to the modern calendar?

AD and BC are used to label the years on the Gregorian calendar, which is the most widely used calendar in the world. The Gregorian calendar is a solar calendar that Pope Gregory XIII introduced in 1582.

What years do AD and BC each cover?

AD starts with year 1 and continues to the present day. BC starts with the year before Christ’s birth, 1 BC, and counts backward to the year 10,000 BC.

What’s the difference between AD and BC vs. CE and BCE?

CE stands for Common Era, and it’s an alternative to AD. BCE stands for Before Common Era, and it’s an alternative to BC.

This blog post was written with the support of Grammarly generative AI.

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