diff --git a/collects/scribblings/reference/stx-ops.scrbl b/collects/scribblings/reference/stx-ops.scrbl
index 999df9cf24..be363d60d0 100644
--- a/collects/scribblings/reference/stx-ops.scrbl
+++ b/collects/scribblings/reference/stx-ops.scrbl
@@ -102,6 +102,8 @@ leaving nested syntax structure (if any) in place.  The result of
 
        @item{an immutable box containing @tech{syntax object}s}
 
+       @item{an immutable @tech{prefab} structure containing @tech{syntax object}s}
+
        @item{some other kind of datum---usually a number, boolean, or string}
 
     }
@@ -130,11 +132,12 @@ are flattened.}
 
 Returns a datum by stripping the lexical information, source-location
 information, properties, and certificates from @scheme[stx]. Inside of
-pairs, (immutable) vectors, and (immutable) boxes, @tech{syntax object}s are
-recursively stripped.
+pairs, (immutable) vectors, (immutable) boxes, and immutable
+@tech{prefab} structures, @tech{syntax object}s are recursively
+stripped.
 
 The stripping operation does not mutate @scheme[stx]; it creates new
-pairs, vectors, and boxes as needed to strip lexical and
+pairs, vectors, boxes, and @tech{prefab} structures as needed to strip lexical and
 source-location information recursively.}
 
 @defproc[(datum->syntax [ctxt (or/c syntax? false/c)]
@@ -155,12 +158,13 @@ source-location information recursively.}
           syntax?]{
 
 Converts the @tech{datum} @scheme[v] to a @tech{syntax object}. If
-@scheme[v] is a pair, vector, or box, then the contents are
-recursively converted; mutable vectors and boxes are essentially
-replaced by immutable vectors and boxes. @tech{Syntax object}s already in
-@scheme[v] are preserved as-is in the result. For any kind of value
-other than a pair, vector, box, or @tech{syntax object}, conversion means
-wrapping the value with lexical information, source-location
+@scheme[v] is a pair, vector, box, or immutable @tech{prefab}
+structure, then the contents are recursively converted; mutable
+vectors and boxes are essentially replaced by immutable vectors and
+boxes. @tech{Syntax object}s already in @scheme[v] are preserved as-is
+in the result. For any kind of value other than a pair, vector, box,
+immutable @tech{prefab} structure, or @tech{syntax object}, conversion
+means wrapping the value with lexical information, source-location
 information, properties, and certificates.
 
 Converted objects in @scheme[v] are given the lexical context
@@ -169,8 +173,8 @@ information of @scheme[ctxt] and the source-location information of
 the resulting immediate @tech{syntax object} is given the properties (see
 @secref["stxprops"]) of @scheme[prop] and the @tech{inactive
 certificates} (see @secref["stxcerts"]) of @scheme[cert]; if
-@scheme[v] is a pair, vector, or box, recursively converted values are
-not given properties or certificates.
+@scheme[v] is a pair, vector, box, or immutable @tech{prefab} structure, 
+recursively converted values are not given properties or certificates.
 
 Any of @scheme[ctxt], @scheme[srcloc], @scheme[prop], or @scheme[cert]
 can be @scheme[#f], in which case the resulting syntax has no lexical
@@ -195,8 +199,8 @@ numbers or both be @scheme[#f], otherwise the
 
 Graph structure is not preserved by the conversion of @scheme[v] to a
 @tech{syntax object}. Instead, @scheme[v] is essentially unfolded into a
-tree. If @scheme[v] has a cycle through pairs, vectors, and boxes,
-then the @exnraise[exn:fail:contract].}
+tree. If @scheme[v] has a cycle through pairs, vectors, boxes, and immutable 
+@tech{prefab} structures, then the @exnraise[exn:fail:contract].}
 
 @defproc[(identifier? [v any/c]) boolean?]{