docs: fix transparent/opaque confusion in the conventions file
diff --git a/docs/conventions.md b/docs/conventions.md
index f86e1e2..c8a39dd 100644
--- a/docs/conventions.md
+++ b/docs/conventions.md
@@ -156,8 +156,8 @@ typedef struct git_odb git_odb;
the library, and not within the application. This allows the type
to grow (or shrink) in size without rebuilding client code.
-To preserve ABI compatibility, include an `int version` field in all opaque
-structures, and initialize to the latest version in the construction call.
+To preserve ABI compatibility, include an `int version` field in all transparent
+structures, and initialize to the latest version in the constructor call.
Increment the "latest" version whenever the structure changes, and try to only
append to the end of the structure.