The lambda symbol seems to be one of the most controversial of symbols
in regards to its meaning. There are several differing opinions as to why
the lambda was chosen as a gay symbol and what it really means. However,
most sources agree on a few things:

     The lambda was first chosen as a gay symbol when it was adopted in 1970
by the New York Gay Activists Alliance. It became the symbol of their growing
movement of gay liberation. In 1974, the lambda was subsequently adopted by
the International Gay Rights Congress held in Edinburgh, Scotland. As their
symbol for lesbian and gay rights, the lambda became internationally popular.

     But where history ends, speculation begins. No one seems to have a
definitive answer why the lambda was originally chosen as a gay symbol. Some
suggest that it is simply the Greek lower-case letter l for liberation. Others
disagree, citing the use of lambda in physics to denote energy (the energy we
have when we work in concert) or wavelength (are gays and lesbians on a
different wavelength?). Lambda may also denote the synergy of the gay movement,
the idea that the whole is greater than the sum of its parts. The lambda also
may represent scales and balance, and the constant force that keeps opposing
sides from overcoming each other -- the hook at the bottom of the right leg
signifies the action needed to reach and maintain balance. The ancient Greek
Spartans regarded the lambda to mean unity, while the Romans considered it "the
light of knowledge shed into the darkness of ignorance." Reportedly, Ancient
Greeks placed the lambda on shields of Spartan warriors, who were often paired
off with younger men in battle. (There was a theory that warriors would fight
more feircely knowing that their lovers were both watching and fighting
alongside them.)

      Whatever the exact meaning and origin, the lambda originally embodied a
fairly militant connotation. Today, the symbol generally denotes lesbian's and
gay men's concerns together. Although the lambda was never intended to be
linked to any specific gender or orientation such as other symbols may be,
historically this is not so: In the early 1970's the Los Angeles gay community
created a flag with a lavender lambda on a simple white background. They hoped
the flag would catch on to other cities, but their hopes were not realized
because some saw the lambda as a male symbol only.