This page describes which Collins-only words are important for an [[OTCWL|OTCWLNWL]] player to learn, and is part of our introduction to [[SOWPODS|Collins (SOWPODS) in North America]]. For brevity, we will refer to the North American and International lexica, OTCWL16 and CSW15, as TWL NWL and CSW respectively.
== How many more words are there, and what would I need to learn? ==
Technically, of course, you need to learn almost nothing, because there are just 59 52 2-8 letter words in TWL NWL that are not in CSW, and almost all of those are obscure. In practice, of course, there are some useful basic words to start with.
Because CSW contains essentially all the TWL NWL words, you can continue to play the same game, and anything that was good in TWL NWL remains good. Because the fundamentals of the game have not changed, the kinds of words that are the most useful to study in TWL NWL are also the best to study in CSW. Thus the player who has studied the 2s, 3s, JQXZ words, some 4s, high probability bingos, etc., can continue to use the same methods for CSW.
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So how many words are there? In total, the TWL contains 188,738 words, and CSW contains 276,663. About half of these are 9–15 letters, and while some 9s can be useful, the vast majority (about 98%) of the gain is with the 2–8s. OWL contains 88,099 of these, while CSW has 118,999, which is 30,900 more. This is about 35%, which means that for approximately every 3 TWL words there is an extra CSW word.
However, it is likely that you did not start out playing TWL with the intention of learning all 188,738 words. Likewise, you can play a good CSW game without needing more than a small fraction of the extra 30,900 2–8s. In fact, you can play a decent game with just the 2s and 3s. The main thing to keep in mind is that essentially every word you know from TWL is still valid. So, as we have already seen that three quarters of the words are TWL, you are already three quarters of the way there. And in many cases, even more than this, because there will be a choice of moves, many of which will be TWL.
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So, what should you actually study? In the following, we present various useful lists and suggestions. In some cases we have presented just the most useful words, but you can see the full list by following the link in the heading.
== Two-letter words ==
As in TWL, by far the most useful words are the 2s. There are 19 20 more of these in CSW:
CH DI EA EE FY GU IO JA KO KY
NY OB OO OU ST UG UR YU ZE ZO
<br>While 19 20 is not a large number, you probably will not remember them all straightaway (your author has played in the World Championships, and did not remember the 2s in one sitting). They will become a natural part of the game over time.
== [[Three-letter words]] ==
Following the 2s, there are 260 267 3s. The most useful 3s are:
QIN EXO IDE OYE JAI ENE ITA AIA IWI AYU
6s: EUOUAE ZOAEAE ZOOEAE
7s: ETAERIO EATERIE AERADIO AIERIES OLEARIA EUGARIE DOULEIA EUOUAES MOINEAU DIANOIA ...
8s: ETAERIOS AEROTONE AEGIRINE NOTITIAE DOUANIER AEGIRITE INAURATE AERADIOS ETOURDIE OLEARIAS ...
== [[Short JQXZ words]] ==
WEXE GREX FAIX DIXI SAXE ...
VITEX VIBEX XOANA JAXIE WEXED ...
Z: ZE ZO
DZO ZOL ZEX ZEA BEZ ...
LAZO TREZ ZITE ZOOT ZATI ...
The basics above are easily enough for a good CSW game. But you may decide that you wish to go further.
A significant downside to going further is that it can be difficult to keep the two lexica separate. Although remembering which of the words you now know are “new” (think back to the last dictionary update, if you have been playing that long) is not too bad, remembering a word and remembering which lexicon it is in are not the same thing, especially over a period of time. Those CSW words may come back to haunt you in a TWL NWL game a few months down the line!
But nevertheless, some people have high ratings at both TWL NWL and CSW, and one can get to quite a high standard quite quickly.
Chosen correctly, it can be shown that learning the top 1% of the words when ordered by playability is equivalent to learning 25% of all the words. So, for the 2-8s, learning the top 300 from CSW is effectively learning one quarter of all the words newly allowed by that lexicon. This top 25% (or any other fraction) can be accessed by playability in the Collins edition of the [[Collins linksNASPA Zyzzyva|Zyzzyva]] word study program.
== Collins Cheat Sheet ==