Prime Words

About

In Scrabble, a prime word (term derived by contrast of a prime number) is a word that is 7 characters or longer that cannot be broken down into a smaller word, to then be completed with less than 7 letters on another turn. By definition, they cannot ever be played on a single turn by adding to a single word nor be gradually built up -- they require the aid of separate words and/or letters on the board (with the exception of 7-lettered words, which can only be played at once on a single move or by hooking to a single letter.)

Hence, the only way to play a prime word is to have the extreme luck of having magically spaced tiles which will complete the word with your 7 or fewer letters, or to play the word in one move by hooking it to the split word or a single tile.

For example: Entrepreneur is a prime word, since the longest word it can be broken down to is "rep", making it impossible to be completed with 7 letters alone on another turn. So the only possible way to ever play this word is to have the board arranged by having separate words and/or "floating" letters on the board with spaces for your rack's letters.

For example, pretending this is a row in the scrabble board:

(E) ( ) ( ) (R E P) ( ) ( ) (N E) ( ) ( )

With your rack being: NTREUR and any other letter (and parentheses being squares in the board.)

Note that if your rack was NTREURS, you could play ENTREPRENEURS and make one astonishing bingo... Unfortunately, anything like this has an astronomically low chance of ever happening in a regular game. Also note that you do not need to complete the word with 7 letters for it to be prime.

Another example: Elephants. Plural or not, you cannot play "ELEPHANT" on a single move because you only have 7 tiles. You could only break this down to "el", so the only way to play this is by having EPHANTS in your rack and hooking on "EL", or by the aid of single tiles positioned on the board.

However, "HANT" is actually a word, thus elephant nor elephants are prime words, for which I made the previous example for mere hypothetical reasons -- also proving that short prime words are quite rare.

A caveat: It may be a misunderstanding that many long words could classify as prime, for example "ELEPHANTIASIS". The longest word which it could be broken to is "ELEPHANT" which is not 7 letters long. But, ELEPHANT can be broken down into HANT. Making the transition HANT -> ELEPHANT -> ELEPHANTIASIS possible without the need of separate tiles on the board and with less than 7 letters on the last move.

If ELEPHANTIASIS were, hypothetically for the sake of example, "ELEPHANTIASIZES", then this would truly be prime: either play the 7 letters from ELEPHANT or have separate words or letters on the board to complete the word. (This is despite the fact that "SIZES" is a word itself, since it has to be separate from our word). The point is that you cannot build it up -- either the whole enchilada at once, fill the gaps or nothing.

It may seem that prime words are pointless, but they're VERY, VERY rare, and quite exotic. Seeing these on a scrabble board on a "natural" game is incredibly rare (or usually involve lots of tile exchanging for the shorter words). And the shorter the word, the harder it is to find them. "Clavicles", despite being abundant in C's and a V, can be broken into "lav", thus not being prime. "Oxyphenbutazone" is indeed a prime word, but a pretty boring one considering it's 15 letters long.