Glossary of maritime terminology
Although there isn't really a standard definition for a 'yacht', as a maritime term it can generally be described as a boat that is used for pleasure or racing. Yachts can be powered both by engine and by wind power - i.e. sailing yachts. Normally a yacht will have a cabin that can be used to sleep in for one or more nights.
Typically speaking, a 'boat' becomes a yacht when it exceeds around 40 feet in overall length. Once a yacht reaches approximately (again there is no set definition) 78 feet in length, it falls into the 'superyacht' category.
Yankee stands for the letter Y in the International Radiotelephony Spelling Alphabet, which is most often referred to as the NATO Phonetic Alphabet or simply the Phonetic Alphabet. This is the most commonly used group of code words used to clearly communicate the letters of the Roman alphabet, particularly over the radio and is essential in helping seafarers give and receive messages, orders and instructions clearly and correctly.