alpha (n.)youdaoicibaDictYouDict[alpha 词源字典]
c. 1300, from Latin alpha, from Greek alpha, from Hebrew or Phoenician aleph (see aleph). The Greeks added -a because Greek words cannot end in most consonants. Sense of "beginning of anything" is from late 14c., often paired with omega (last letter in the Greek alphabet) as "the end." Sense of "first in a sequence" is from 1620s. Alpha male was in use by c. 1960 among scientists studying animals; applied to humans in society from c. 1992.[alpha etymology, alpha origin, 英语词源]