Answer:
Strait.
Step-by-step explanation:
After a fast online search, I've found that the list of words are:
Athens
Age of Pericles
satraps
tyrant
Cyrus the Great
hoplites
Parthenon
peninsula
upper-class Athenian women
strait
Well, the definition is:
"A narrow body of water with land on both sides"
This is something like a river, so we need to find which one of these words means something like river.
To do it, let's look at short definitions of each word:
Athens: This is the capital city of Grece. (Isn't the correct option)
Age of Pericles: This refers to a historical period (isn't the correct option)
Satraps: Were governors in the Persian empire (Isn't the correct option)
Tyrant: Refers to a cruel leader (Isn't the correct option)
Cyrus the Great: Was the founder of the Achaemenid Empire (isn't the correct option)
Hoplites: A citizen-soldier (isn't the correct option)
Parthenon: A construction in Grece (isn't the correct option)
Peninsula: A small body of land surrounded mostly by water, but connected to land (isn't the correct option)
upper-class Athenian women: It is self-explained, this isn't the correct option.
Strait: This refers to a narrow passage of water that connects two larger areas of water (like two seas, for example)
Then this one is the correct option.