Shellbacks and polliwogs
My brother and his girlfriend are currently polliwogs, but sometime today or tomorrow they will become shellbacks. A polliwog or pollywog is a sailor who has not crossed the equator, while a shellback is one who has, or an experienced or old sailor.
According to nautical tradition, when the equator is crossed, a ceremony is performed for King Neptune and shellbacks ridicule and humiliate polliwogs.
Polliwog comes from the Middle English polwygle. Pol comes from Middle Low German polle, hair of the head, head, top of a tree, and wygle from Middle Low German, Middle Dutch wiggeln.
There’s some details of the equator crossing ceremonies in the US navy at: http://www.desausa.org/pollywog_to_shellback.htm
And you can follow my brother’s adventures at: