Laconic

Laconic: adj: 1. using few words; expressing much in few words; concise: a laconic reply. origin: 1580s, probably via Latin Laconicus, from Greek Lakonikos, from Lakon "person from Lakonia," the district around Sparta in southern Greece in ancient times, whose inhabitants were famously proud of their brevity of speech.

A story:

Philip II of Macedon was consolidating his military position in Greece. After invading southern Greece and receiving the submission of other major city-states, he turned his attention to Sparta and asked, with bad intent, whether he should come as friend or foe.

“Neither,” was the reply.
He then sent this message:
“You are advised to submit without further delay, for if I bring my army into your land, I will destroy your farms, slay your people, and raze your city”
The Spartans again replied with a single word:
“If.”