Lambda

In the early 1970s, in the wake of Stonewall, New York's Gay Activists Alliance adopted the Greek letter lambda — suggested by member Tom Doerr for its scientific use denoting kinetic potential — as its emblem. The symbol spread widely, sometimes worn as a discreet amulet recognizable within the community but unremarkable outside it.

The lowercase lambda carries layered meaning: to the Greeks, scales and balance; the hook at its base, the effort required to maintain that balance; to the Spartans, unity and a society that shouldn't infringe on individual freedom; to the Romans, the light of knowledge in darkness; in physics, an energy change. Ancient Greek soldiers are also reported to have carried the lambda on the shields of gay men and their lovers within the fighting elite of the Greek army.