diff --git a/lib/Quox/Definition.idr b/lib/Quox/Definition.idr
index a434cdc..41e426c 100644
--- a/lib/Quox/Definition.idr
+++ b/lib/Quox/Definition.idr
@@ -12,12 +12,18 @@ record AnyTerm q where
   constructor T
   get : forall d, n. Term q d n
 
+
+public export
+data DefBody q =
+    Concrete (AnyTerm q)
+  | Postulate
+
 public export
 record Definition' q (isGlobal : Pred q) where
-  constructor MkDef'
+  constructor MkDef
   qty  : q
   type : AnyTerm q
-  term : Maybe $ AnyTerm q
+  body : DefBody q
   {auto 0 qtyGlobal : isGlobal qty}
 
 public export
@@ -27,12 +33,12 @@ Definition q = Definition' q IsGlobal
 public export %inline
 mkDef : IsQty q => (qty : q) -> (0 _ : IsGlobal qty) =>
         (type, term : forall d, n. Term q d n) -> Definition q
-mkDef qty type term = MkDef' {qty, type = T type, term = Just (T term)}
+mkDef qty type term = MkDef {qty, type = T type, body = Concrete (T term)}
 
 public export %inline
-mkAbstract : IsQty q => (qty : q) -> (0 _ : IsGlobal qty) =>
+mkPostulate : IsQty q => (qty : q) -> (0 _ : IsGlobal qty) =>
              (type : forall d, n. Term q d n) -> Definition q
-mkAbstract qty type = MkDef' {qty, type = T type, term = Nothing}
+mkPostulate qty type = MkDef {qty, type = T type, body = Postulate}
 
 
 public export %inline
@@ -43,9 +49,15 @@ public export %inline
 (.type0) : Definition' q _ -> Term q 0 0
 g.type0 = g.type.get
 
+public export %inline
+(.term) : Definition' q _ -> Maybe (AnyTerm q)
+g.term = case g.body of
+  Concrete t => Just t
+  Postulate  => Nothing
+
 public export %inline
 (.term0) : Definition' q _ -> Maybe (Term q 0 0)
-g.term0 = map (\t => t.get) g.term
+g.term0 = map (\x => x.get) g.term
 
 public export %inline
 (.qtyP) : forall q, isGlobal. Definition' q isGlobal -> Subset q isGlobal
diff --git a/tests/Tests/Equal.idr b/tests/Tests/Equal.idr
index eef697d..af52df0 100644
--- a/tests/Tests/Equal.idr
+++ b/tests/Tests/Equal.idr
@@ -10,14 +10,14 @@ M = ReaderT (Definitions Three) (Either (Error Three))
 
 defGlobals : Definitions Three
 defGlobals = fromList
-  [("A", mkAbstract Zero $ TYPE 0),
-   ("B", mkAbstract Zero $ TYPE 0),
-   ("a", mkAbstract Any $ FT "A"),
-   ("a'", mkAbstract Any $ FT "A"),
-   ("b", mkAbstract Any $ FT "B"),
-   ("f", mkAbstract Any $ Arr One (FT "A") (FT "A")),
+  [("A", mkPostulate Zero $ TYPE 0),
+   ("B", mkPostulate Zero $ TYPE 0),
+   ("a", mkPostulate Any $ FT "A"),
+   ("a'", mkPostulate Any $ FT "A"),
+   ("b", mkPostulate Any $ FT "B"),
+   ("f", mkPostulate Any $ Arr One (FT "A") (FT "A")),
    ("id", mkDef Any (Arr One (FT "A") (FT "A")) (["x"] :\\ BVT 0)),
-   ("eq-AB", mkAbstract Zero $ Eq0 (TYPE 0) (FT "A") (FT "B"))]
+   ("eq-AB", mkPostulate Zero $ Eq0 (TYPE 0) (FT "A") (FT "B"))]
 
 parameters (label : String) (act : Lazy (M ()))
            {default defGlobals globals : Definitions Three}
@@ -176,7 +176,7 @@ tests = "equality & subtyping" :- [
 
     testEq "p : (a ≡ a' : A), q : (a ≡ a' : A) ∥ ⊢ p = q  (free)"
            {globals =
-              let def = mkAbstract Zero $ Eq0 (FT "A") (FT "a") (FT "a'") in
+              let def = mkPostulate Zero $ Eq0 (FT "A") (FT "a") (FT "a'") in
               defGlobals `mergeLeft` fromList [("p", def), ("q", def)]} $
       equalE empty (F "p") (F "q"),
 
diff --git a/tests/Tests/Typechecker.idr b/tests/Tests/Typechecker.idr
index 444d4ff..6483e87 100644
--- a/tests/Tests/Typechecker.idr
+++ b/tests/Tests/Typechecker.idr
@@ -72,19 +72,19 @@ sndDef =
 
 defGlobals : Definitions Three
 defGlobals = fromList
-  [("A",  mkAbstract Zero $ TYPE 0),
-   ("B",  mkAbstract Zero $ TYPE 0),
-   ("C",  mkAbstract Zero $ TYPE 1),
-   ("D",  mkAbstract Zero $ TYPE 1),
-   ("P",  mkAbstract Zero $ Arr Any (FT "A") (TYPE 0)),
-   ("a",  mkAbstract Any  $ FT "A"),
-   ("a'", mkAbstract Any  $ FT "A"),
-   ("b",  mkAbstract Any  $ FT "B"),
-   ("f",  mkAbstract Any  $ Arr One (FT "A") (FT "A")),
-   ("g",  mkAbstract Any  $ Arr One (FT "A") (FT "B")),
-   ("f2", mkAbstract Any  $ Arr One (FT "A") $ Arr One (FT "A") (FT "B")),
-   ("p",  mkAbstract Any  $ Pi_ One "x" (FT "A") $ E $ F "P" :@ BVT 0),
-   ("q",  mkAbstract Any  $ Pi_ One "x" (FT "A") $ E $ F "P" :@ BVT 0),
+  [("A",  mkPostulate Zero $ TYPE 0),
+   ("B",  mkPostulate Zero $ TYPE 0),
+   ("C",  mkPostulate Zero $ TYPE 1),
+   ("D",  mkPostulate Zero $ TYPE 1),
+   ("P",  mkPostulate Zero $ Arr Any (FT "A") (TYPE 0)),
+   ("a",  mkPostulate Any  $ FT "A"),
+   ("a'", mkPostulate Any  $ FT "A"),
+   ("b",  mkPostulate Any  $ FT "B"),
+   ("f",  mkPostulate Any  $ Arr One (FT "A") (FT "A")),
+   ("g",  mkPostulate Any  $ Arr One (FT "A") (FT "B")),
+   ("f2", mkPostulate Any  $ Arr One (FT "A") $ Arr One (FT "A") (FT "B")),
+   ("p",  mkPostulate Any  $ Pi_ One "x" (FT "A") $ E $ F "P" :@ BVT 0),
+   ("q",  mkPostulate Any  $ Pi_ One "x" (FT "A") $ E $ F "P" :@ BVT 0),
    ("refl", mkDef Any reflTy reflDef),
    ("fst",  mkDef Any fstTy fstDef),
    ("snd",  mkDef Any sndTy sndDef)]