Is “Appendix” a Scrabble word?
Yes
APPENDIX
Valid in at least one Scrabble dictionary
Valid in these dictionaries
SOWPODS / CSW
Scrabble UK & International
TWL / NWL
Scrabble North America
Large English Dictionary
General English word list
Meaning of Appendix
/əˈpɛn.dɪks/
noun
1.Something attached to something else; an attachment or accompaniment.
2.A text added to the end of a book or an article, containing additional information.
3.The vermiform appendix, an inner organ that can become inflamed.
Synonyms: addition, attachment