αιώνας

From Ancient Greek αἰών (aiṓn, “epoch”).

αιώνας • (aiónas) m (plural αιώνες)

1. century (100 consecutive years)

   Synonym: εκατονταετία (ekatontaetía)

2. century (specifically a numbered period with conventional start)

   Synonym: (abbrev.) αι. (ai.)

   Έγινε στα μέσα του 20ου αιώνα.

   Égine sta mésa tou 20ou aióna.

   It took place in the middle of the 20th century.

3. (geology) eon, era, age

   Φανεροζωικός αιώνας ― Fanerozoïkós aiónas ― Phanerozoic eon

4. eternity, age, eon

"Proterozoic eon" will be found translated as Προτεροζωικός αιώνας (Proterozoïkós aiónas) and Προτεροζωικός μεγααιώνας (Proterozoïkós megaaiónas). The form αιώνας (aiónas) can mean any long period (age, century, etc) so μεγααιώνας (megaaiónas, “large eon”) is often used to make the meaning clear.

• (eon): μεγααιώνας m (megaaiónas) (geological timescale)

• see: έτος n (étos, “year”)