Collins Scrabble Words is a list of allowable words according to certain criteria.

Criteria

• Does not include proper nouns, place names, and words with an initial capital letter, unless such words can also be spelt with a lowercase initial letter
• Does not include abbreviations, prefixes, suffixes, words requiring apostrophes or hyphens
• Includes foreign words that are considered to have been absorbed into the English language
• Includes inflected forms, such as plurals and verb forms, eg plumb, plumbs, plumbed, plumbing
• Includes words that are old, obsolete, dialectal, historical and/or literary
• Includes World English, including spelling and variants from the US, South Africa, Australia, New Zealand, etc
• Includes words that are denoted contractions, short forms and slang
• Includes words which may be deemed rude or offensive.

The sources used are

• Collins English Dictionary 14^th edition
• Legacy words from OSW which used Chambers Dictionary (about 16 000 words)
• North American Scrabble Players Association Word List 2023

The list of allowable words is usually updated every five years. Since the fifth edition (CSW19) there was an intercalary sixth edition whose purpose was to expunge over 400 words whose sole definition is derogatory or demeaning.

The seventh edition (CSW24) will be available in Australia in late January. Buy from Amazon $36.62 or Harper Collins $45. It has words up to 15 letters long, including inflected forms. There are more than 290,000 words.
It is likely that all states and territories of Australia will use CSW24 from Jan 1 2025.

There are electronic resources which can be used to check words, do postmortems and generate special lists. At this date, the following have options for several lexicons including CSW24.

• Computers
  • Zyzzyva MacOS
  • Zyzzyva Windows 64 bit

• iOS
  • Zyzzyva
  • ULU
• Android
  • Zyzzyva
  • Word App Pro

Chris Lipe, the WESPA Chair created an Initiation Kit which states This update to the official tournament word list features 1,814 new words, 845 of which are between three and eight letters in length. Tony Kalayzich and David Sutton created a supplemental Complete New Words
The cross-tables.com site has a handy list of what they unfortunately call a cheat sheet which could be printed as one double sided page.

Printable lists

Here are some lists for CSW24 suitable for printing. Each list will open in your browser, and you print it from there. By using a judicious adjustment of scale, margins, omitting headers, orientation and so on, you can get it how you like. You could even print to a PDF. CSW21 deletions are grey, CSW24 additions are bold.