diff --git a/core/src/main/java/org/everit/json/schema/ObjectSchema.java b/core/src/main/java/org/everit/json/schema/ObjectSchema.java
index 3f13851c..cc78d259 100644
--- a/core/src/main/java/org/everit/json/schema/ObjectSchema.java
+++ b/core/src/main/java/org/everit/json/schema/ObjectSchema.java
@@ -39,6 +39,8 @@ private static final Regexp toRegexp(String pattern) {
 
         private boolean requiresObject = true;
 
+        private final Map<String, Schema> definitionSchemas = new HashMap<>();
+
         private final Map<String, Schema> propertySchemas = new HashMap<>();
 
         private boolean additionalProperties = true;
@@ -64,6 +66,22 @@ public Builder additionalProperties(boolean additionalProperties) {
             return this;
         }
 
+        /**
+         * Adds a definition schema.
+         *
+         * @param definitionName
+         *         the name of the definition
+         * @param schema
+         *         the definition of the {@code schema}
+         * @return {@code this}
+         */
+        public Builder addDefinitionSchema(String definitionName, Schema schema) {
+            requireNonNull(definitionName, "definitionName cannot be null");
+            requireNonNull(schema, "schema cannot be null");
+            definitionSchemas.put(definitionName, schema);
+            return this;
+        }
+
         /**
          * Adds a property schema.
          *
@@ -170,6 +188,8 @@ private static <K, V> Map<K, V> copyMap(Map<K, V> original) {
         return Collections.unmodifiableMap(new HashMap<>(original));
     }
 
+    private final Map<String, Schema> definitionSchemas;
+
     private final Map<String, Schema> propertySchemas;
 
     private final boolean additionalProperties;
@@ -202,8 +222,10 @@ private static <K, V> Map<K, V> copyMap(Map<K, V> original) {
      */
     public ObjectSchema(Builder builder) {
         super(builder);
+        this.definitionSchemas = builder.definitionSchemas == null ? null
+                : Collections.unmodifiableMap(builder.definitionSchemas);
         this.propertySchemas = builder.propertySchemas == null ? null
-                : Collections.unmodifiableMap(builder.propertySchemas);
+            : Collections.unmodifiableMap(builder.propertySchemas);
         this.additionalProperties = builder.additionalProperties;
         this.schemaOfAdditionalProperties = builder.schemaOfAdditionalProperties;
         if (!additionalProperties && schemaOfAdditionalProperties != null) {
@@ -248,6 +270,10 @@ public Map<String, Set<String>> getPropertyDependencies() {
         return propertyDependencies;
     }
 
+    public Map<String, Schema> getDefinitionSchemas() {
+        return definitionSchemas;
+    }
+
     public Map<String, Schema> getPropertySchemas() {
         return propertySchemas;
     }
@@ -344,6 +370,7 @@ public boolean equals(Object o) {
             return that.canEqual(this) &&
                     additionalProperties == that.additionalProperties &&
                     requiresObject == that.requiresObject &&
+                    Objects.equals(definitionSchemas, that.definitionSchemas) &&
                     Objects.equals(propertySchemas, that.propertySchemas) &&
                     Objects.equals(schemaOfAdditionalProperties, that.schemaOfAdditionalProperties) &&
                     Objects.equals(requiredProperties, that.requiredProperties) &&
@@ -362,7 +389,7 @@ public boolean equals(Object o) {
 
     @Override
     public int hashCode() {
-        return Objects.hash(super.hashCode(), propertySchemas, propertyNameSchema, additionalProperties,
+        return Objects.hash(super.hashCode(), definitionSchemas, propertySchemas, propertyNameSchema, additionalProperties,
                 schemaOfAdditionalProperties, requiredProperties, minProperties, maxProperties, propertyDependencies,
                 schemaDependencies, requiresObject, patternProperties, oneOrMoreDefaultProperty);
     }
diff --git a/core/src/main/java/org/everit/json/schema/ToStringVisitor.java b/core/src/main/java/org/everit/json/schema/ToStringVisitor.java
index a66d69be..262b4c15 100644
--- a/core/src/main/java/org/everit/json/schema/ToStringVisitor.java
+++ b/core/src/main/java/org/everit/json/schema/ToStringVisitor.java
@@ -227,6 +227,13 @@ private void describePropertyDependencies(Map<String, Set<String>> propertyDepen
         visit(propertyNameSchema);
     }
 
+    @Override void visitDefinitionSchemas(Map<String, Schema> definitionSchemas) {
+        if (!definitionSchemas.isEmpty()) {
+            writer.key("definitions");
+            printSchemaMap(definitionSchemas);
+        }
+    }
+
     @Override void visitPropertySchemas(Map<String, Schema> propertySchemas) {
         if (!propertySchemas.isEmpty()) {
             writer.key("properties");
diff --git a/core/src/main/java/org/everit/json/schema/Visitor.java b/core/src/main/java/org/everit/json/schema/Visitor.java
index baef5333..1a853593 100644
--- a/core/src/main/java/org/everit/json/schema/Visitor.java
+++ b/core/src/main/java/org/everit/json/schema/Visitor.java
@@ -159,6 +159,10 @@ void visitObjectSchema(ObjectSchema objectSchema) {
         for (Map.Entry<String, Schema> schemaDep : objectSchema.getSchemaDependencies().entrySet()) {
             visitSchemaDependency(schemaDep.getKey(), schemaDep.getValue());
         }
+        Map<String, Schema> definitionSchemas = objectSchema.getDefinitionSchemas();
+        if (definitionSchemas != null) {
+            visitDefinitionSchemas(definitionSchemas);
+        }
         Map<String, Schema> propertySchemas = objectSchema.getPropertySchemas();
         if (propertySchemas != null) {
             visitPropertySchemas(propertySchemas);
@@ -177,6 +181,12 @@ void visitPatternProperties(Map<Regexp, Schema> patternProperties) {
         }
     }
 
+    void visitDefinitionSchemas(Map<String, Schema> definitionSchemas) {
+        for (Map.Entry<String, Schema> entry : definitionSchemas.entrySet()) {
+            visitPropertySchema(entry.getKey(), entry.getValue());
+        }
+    }
+
     void visitPropertySchemas(Map<String, Schema> propertySchemas) {
         for (Map.Entry<String, Schema> entry : propertySchemas.entrySet()) {
             visitPropertySchema(entry.getKey(), entry.getValue());