A note about "grain" and "figure". These terms are used in sometimes interchangeably in a way that I believe to be incorrect. In this glossary, I take a point of view which I believe is the "correct" one, but I want to acknowledge that it is opposed to that taken by some, including a man whom I consider very much my better in regards to knowledge of wood and that is Dr. Bruce Hoadley who has written two books that are widely, and I believe appropriately, considered to be the definitive works in their field. These are "Identifying Wood" and "Understanding Wood". On this particular issue, I have a strong and supportable reason for differing with Dr. Hoadley.
What is presented below is first a discussion of how I see the two terms and why, and following that an extensive list of the causes for figure and the types of figure.
Had this difference of opinion been with anyone other than Dr. Hoadley, I would simply have ignored them and gone on my way and would not have subjected my readers to this diatribe. However, I think that regarding ANY other information about wood, anyone who ignores Dr. Hoadley is being foolish. As young people say these days, when it comes to knowledge about wood, "He da man".