Academy
An academy (Attic Greek: Ἀκαδήμεια; Koine Greek Ἀκαδημία) is an institution of secondary education, higher learning, research, or honorary membership. The term academia refers to the worldwide human group composed of professors and researchers at institutes of higher learning.
Sigma
Sigma (upper-case Σ, lower-case σ, lower-case in word-final position ς; Greek: σίγμα) is the eighteenth letter of the Greek alphabet. In the system of Greek numerals, it has a value of 200. When used at the end of a word (when the word is not all caps), the final form (ς) is used, e.g. Ὀδυσσεύς (Odysseus); note the two sigmas in the center of the name, and the word-final sigma at the end.