noun
Usage: sometimes capitalized O&S&T
1.
a. : a necktie displaying the colors of an English public school
entitled to wear the very best of old school ties, the Etonian pale blue and black — Fortune
b. : an attitude of conservatism, aplomb, and upper-class solidarity associated with English public school graduates
the traditional prejudice against the British, their aristocratic society and their old school ties — Atlantic
c. : a graduate of an English public school
to the old school ties the dictators seem ignorant uneducated rebels — G.B.Shaw
2. : clannishness , cliquism
the War and Navy departments each accumulated growing prestige which fostered the spirit of the old school tie — Beirne Lay