The sign is formed by holding down the thumb and little finger on the right hand, leaving the three middle fingers extended. These three fingers represent the three parts of the Girl Scout Promise.

Girl Scout Handshake
This is the way many Girl Scouts and Girl Guides greet each other. They shake their left hands while making the Girl Scout sign with their right hand. The left handed handshake represents friendship because the left hand is closer to the heart than the right.
Quiet Sign
In order to maintain order at lively Girl Scout functions, the leader raises her right hand for silence. The girls follow in the motion; as their hands go up, the conversation stops, until everyone has their hand up and the room is silent.
Friendship Circle
The friendship circle is often formed at the end of meetings or campfires as a sort of closing ceremony. Everyone gathers in a circle where they cross their right arm over their left in front of them and hold hands with the people on either side. Once everyone is silent, the leader starts the friendship squeeze which is passed from hand to hand. Often the girls will make a wish after their hand has been squeezed before they pass the squeeze along. Also, in some larger groups, the girls put their
right foot out into the circle when they receive the friendship squeeze, so that everyone can see it travel along the circle.
Girl Scout Slogan
Do a good turn daily.
Girl Scout Motto
Be prepared.
Jargon:
Activity Patch - The patches girls earn by attending events, i.e International Day celebration, Camporee, etc. These patches may go on the back of the sash or vest. They can also be put on a jacket or tote bag.
Age Level - There are five age levels in Girl Scouting: Daisy, Brownie, Junior, Cadette, Senior.
Bridging - A ceremony for girls leaving one level of Girl Scouting and moving into the next. For example, Brownies 'fly up' into Juniors.
Brownie Ring - Form of Government commonly used in a Brownie Troop.
Buddy System - A safety system where two girls stay together and watch out for each other.
Court of Awards - A ceremony in which girls and/or adult volunteers receive recognitions. Recognitions can include earned proficiency awards (Try-its, etc), activity patches from events (such as Camporee or Int'l Day), etc.
Dunk Bag - A mesh bag into which a scout puts her washed camp dishes and silverware. Holding the pull cord she dunks the bag into boiling water for the prescribed sterilization time, then hangs it on a line to dry.
Flag Ceremony - Any ceremony including or honoring the flag.
Fly-up - The ceremony in which a Brownie becomes a Junior Scout.
Founder's Day - October 31, the birthday of Juliette Low.
Friendship Circle - A symbolic gesture in which Girl Scouts form a circle by clasping each other's hands. It is often used at a closing ceremony.
Girl Guides - The original name for Girl Scouts, still used in many countries.
Girl Scout Birthday - March 12th, the date of the first Girl Scout meeting in the USA in 1912.
GORP - 'Good Old Raisins and Peanuts', a trail mix snack.
Investiture - A special ceremony to welcome a girl Scout where she receives her pin and officially makes her Promise for the first time.
Juliette Daisy Low - Founder of Girl Scouting in the U.S.A.
Juliette Low World Friendship Fund – A voluntary fund that benefits guiding throughout the world.
Kaper Chart - A chart showing all jobs available and who is responsible for each job generally on a rotating basis.
Leader Appreciation Day – April 22, a special day to honor Girl Scout leaders.
Mess Kit - Non-breakable plate, cup, bowl and silverware (knife, fork and spoon) to be used as a place setting when eating meals.
Motto - Be Prepared.
Quiet Sign - Right hand raised above head - it means stop talking.
Rededication - A ceremony when Girl Scouts reaffirm their belief in the Promise and Law.
Scout's Own - A quiet inspirational ceremony that has a theme and is planned by Girl Scouts and their leaders.
Sit Upon - A 'cushion' made by Girl Scouts to use when the ground is damp or to keep their clothes clean.
Slogan - 'Do a good turn daily.'
SWAPS - Small Whatchamacallit Affectionately Pinned on Somewhere. These are used as a small souvenir from the different troops that have attended an event. During the event there is usually a time when the girls scatter and find other girls to trade swaps with.
Thinking Day – February 22nd, a time to think of our sister Scouts and Guide around the world.
Trefoil - The international symbol of Girl Scouting. The three leaves of the trefoil represent the three parts of the promise.
Try-It - Triangular embroidered recognition for Brownie Girl Scouts.
WAGGGS – World Association for Girl Guides and Girl Scouts
Wide Game - An activity with a purpose which takes place by going through a series of stations (either manned or unmanned) and completing the instructions at each station.
World Centers - Four program activity centers owned by WAGGGS. The centers are located in Mexico, England, India, and Switzerland.
Ceremonies
FLAG CEREMONIES - Inherent in the Girl Scout Promise is our belief in service to our country. To that end, Flag Ceremonies are used to display our respect for that very important symbol of our nation. Often times, Flag Ceremonies are used to open a meeting or are used as part of a larger ceremony. However they are used, proper respect for our flag should always been shown. Whether you use a "fun-type" ceremony (such as Recipe for a Flag) or a more reverent one, the main criteria is that the ceremony should show this respect.

CANDLE CEREMONIES - Candlelighting Ceremonies are very traditional in Girl Scouting. When used as part of an Investiture or Rededication Ceremony, the candles represent parts of the Promise and Law. Candlelighting Ceremonies can also be done with the candles representing other things as well. The limit is only the girls' imagination. If a ceremony of this type is desired for younger girls, an alternate solution would be to use flashlights with colored tissue paper covering the lights instead of different colors of candles.
GIRL SCOUTS' OWN CEREMONY - A Girl Scouts' Own Ceremony is in fact just that - the girls' own ceremony. Based around a central theme, it is an inspirational and reflective ceremony that the girls plan and implement themselves. Themes may be taken from nature (water, trees, wind, etc.), different things we value (friendship, family, etc.) or even the Girl Scout Promise and Law itself. These ceremonies may be done at any time the girls would like to express their feelings. Many times, Girl Scouts' Owns are done as a closing to camp but they can be easily done at a troop meeting as well.

COURT OF AWARDS CEREMONY - Sometimes a large part of our program is based around the girls earning recognitions. Presentation of these recognitions is done at a Court of Awards Ceremony. If many recognitions are earned during the year, it may prove beneficial to have Court of Awards Ceremonies several times throughout the year. Likewise, if girls are bridging to a new level, receiving their recognitions in a timely manner so that they can be worn on their current uniform is also a good idea.
INVESTITURE & REDEDICATION - An Investiture Ceremony is held to welcome a new girl into the Girl Scouting movement. A Rededication Ceremony is used to reaffirm belief in the Girl Scout Promise and Law. Since the Promise and Law are the very foundation of Girl Scouts, it is very appropriate to hold this ceremony at least once a year. It can be combined with an Investiture Ceremony if there is a combination of new and continuing girls within a troop.

THINKING DAY - February 22, the common birthday of Lord and Lady Baden-Powell, is known as Thinking Day. This is a day set aside throughout the world for Scouts and Guides to remember each other. It is commonly a time to explore other cultures and talk about world friendship and peace. Since Girl Scouts and Girl Guides belong to WAGGGS (World Association of Girl Guides and Girl Scouts), this is also an appropriate time to present the World Association Pin to invested Girl Scouts as well as discuss its meaning.
BRIDGING - A Bridging Ceremony is held any time a girl moves from one age level to the next, i.e., Daisies to Brownies, Brownies to Juniors , Juniors to Cadettes, Cadettes to Seniors, and Seniors to Adults. A Brownie Bridging Ceremony is commonly called a "Fly/Up Ceremony" because the girl is entitled to receive her Brownie Girl Scout Wings. Any girl who was previously a Brownie Girl Scout is entitled to wear her wings. The Bridging patches available at each level need not be earned in order for a girl to bridge. She bridges whether or not she has completed the requirements to earn the Bridging Patch.

Information courtesy Bedford-Hanscom Girl Scouts