book: add DST to glossary

diff --git a/src/doc/trpl/glossary.md b/src/doc/trpl/glossary.md
index 307aef8018066827593cb2b2c542dda63e26e069..6a5a45fdb2c4412893455999eacbd64aa119b5a8 100644 (file)
--- a/src/doc/trpl/glossary.md
+++ b/src/doc/trpl/glossary.md
@@ -38,6 +38,12 @@ let z = (8, 2, 6);
 
 In the example above `x` and `y` have arity 2. `z` has arity 3.
 
+### DST (Dynamically Sized Type)
+
+A type without a statically known size or alignment. ([more info][link])
+
+[link]: ../nomicon/exotic-sizes.html#dynamically-sized-types-(dsts)
+
 ### Expression
 
 In computer programming, an expression is a combination of values, constants,