|Centuries:||1st century – 2nd century – 3rd century|
|Decades:||110s 120s 130s – 140s – 150s 160s 170s|
|Years:||137 138 139 – 140 – 141 142 143|
|140 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishment and disestablishment categories|
|Establishments – Disestablishments|
|Ab urbe condita||893|
|Chinese calendar||己卯年 (Earth Rabbit)
2836 or 2776
— to —
庚辰年 (Metal Dragon)
2837 or 2777
|Coptic calendar||−144 – −143|
|- Vikram Samvat||196–197|
|- Shaka Samvat||62–63|
|- Kali Yuga||3241–3242|
|Iranian calendar||482 BP – 481 BP|
|Islamic calendar||497 BH – 496 BH|
|Minguo calendar||1772 before ROC
|Seleucid era||451/452 AG|
|Thai solar calendar||682–683|
Year 140 (CXL) was a leap year starting on Thursday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Hadrianus and Caesar (or, less frequently, year 893 Ab urbe condita). The denomination 140 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
- Emperor Antoninus Augustus Pius and Marcus Aurelius Caesar become Roman Consuls.
- Antoninus Pius recognizes the king of the Quadi, who becomes an ally of Rome.
- King Mithridates IV dies, Vologases III claims the throne and extended his rule through the Parthian Empire.
- The export of olive oil from Hispania Baetica to Rome peaks.
- Pope Pius I succeeds Pope Hyginus as the tenth pope.
- Marcion arrives in Rome, bringing Evangelikon and Apostolikon to the Christian community.
Arts and sciences
- Faustina the Elder, Roman Empress and wife of Antoninus Pius (b. c. 100 AD)
- Mithridates IV, king of Parthia (b. 109)