diff --git a/src/main/java/io/reactivex/functions/Function3.java b/src/main/java/io/reactivex/functions/Function3.java
index 2f4836c763..f3b49d8a69 100644
--- a/src/main/java/io/reactivex/functions/Function3.java
+++ b/src/main/java/io/reactivex/functions/Function3.java
@@ -19,7 +19,7 @@
  * A functional interface (callback) that computes a value based on multiple input values.
  * @param <T1> the first value type
  * @param <T2> the second value type
- * @param <T3> the second value type
+ * @param <T3> the third value type
  * @param <R> the result type
  */
 public interface Function3<T1, T2, T3, R> {
diff --git a/src/main/java/io/reactivex/functions/Function4.java b/src/main/java/io/reactivex/functions/Function4.java
index 3db600d9d4..70e921d2dd 100644
--- a/src/main/java/io/reactivex/functions/Function4.java
+++ b/src/main/java/io/reactivex/functions/Function4.java
@@ -19,8 +19,8 @@
  * A functional interface (callback) that computes a value based on multiple input values.
  * @param <T1> the first value type
  * @param <T2> the second value type
- * @param <T3> the second value type
- * @param <T4> the second value type
+ * @param <T3> the third value type
+ * @param <T4> the fourth value type
  * @param <R> the result type
  */
 public interface Function4<T1, T2, T3, T4, R> {
diff --git a/src/main/java/io/reactivex/functions/Function5.java b/src/main/java/io/reactivex/functions/Function5.java
index bcdaac3721..32ccfe16d3 100644
--- a/src/main/java/io/reactivex/functions/Function5.java
+++ b/src/main/java/io/reactivex/functions/Function5.java
@@ -19,9 +19,9 @@
  * A functional interface (callback) that computes a value based on multiple input values.
  * @param <T1> the first value type
  * @param <T2> the second value type
- * @param <T3> the second value type
- * @param <T4> the second value type
- * @param <T5> the second value type
+ * @param <T3> the third value type
+ * @param <T4> the fourth value type
+ * @param <T5> the fifth value type
  * @param <R> the result type
  */
 public interface Function5<T1, T2, T3, T4, T5, R> {
diff --git a/src/main/java/io/reactivex/functions/Function6.java b/src/main/java/io/reactivex/functions/Function6.java
index 29d7ceb34a..c011545c98 100644
--- a/src/main/java/io/reactivex/functions/Function6.java
+++ b/src/main/java/io/reactivex/functions/Function6.java
@@ -19,10 +19,10 @@
  * A functional interface (callback) that computes a value based on multiple input values.
  * @param <T1> the first value type
  * @param <T2> the second value type
- * @param <T3> the second value type
- * @param <T4> the second value type
- * @param <T5> the second value type
- * @param <T6> the second value type
+ * @param <T3> the third value type
+ * @param <T4> the fourth value type
+ * @param <T5> the fifth value type
+ * @param <T6> the sixth value type
  * @param <R> the result type
  */
 public interface Function6<T1, T2, T3, T4, T5, T6, R> {
diff --git a/src/main/java/io/reactivex/functions/Function7.java b/src/main/java/io/reactivex/functions/Function7.java
index 981136fd21..bb8dee9ed3 100644
--- a/src/main/java/io/reactivex/functions/Function7.java
+++ b/src/main/java/io/reactivex/functions/Function7.java
@@ -19,11 +19,11 @@
  * A functional interface (callback) that computes a value based on multiple input values.
  * @param <T1> the first value type
  * @param <T2> the second value type
- * @param <T3> the second value type
- * @param <T4> the second value type
- * @param <T5> the second value type
- * @param <T6> the second value type
- * @param <T7> the second value type
+ * @param <T3> the third value type
+ * @param <T4> the fourth value type
+ * @param <T5> the fifth value type
+ * @param <T6> the sixth value type
+ * @param <T7> the seventh value type
  * @param <R> the result type
  */
 public interface Function7<T1, T2, T3, T4, T5, T6, T7, R> {
diff --git a/src/main/java/io/reactivex/functions/Function8.java b/src/main/java/io/reactivex/functions/Function8.java
index 5374d27968..8b8785ea91 100644
--- a/src/main/java/io/reactivex/functions/Function8.java
+++ b/src/main/java/io/reactivex/functions/Function8.java
@@ -19,12 +19,12 @@
  * A functional interface (callback) that computes a value based on multiple input values.
  * @param <T1> the first value type
  * @param <T2> the second value type
- * @param <T3> the second value type
- * @param <T4> the second value type
- * @param <T5> the second value type
- * @param <T6> the second value type
- * @param <T7> the second value type
- * @param <T8> the second value type
+ * @param <T3> the third value type
+ * @param <T4> the fourth value type
+ * @param <T5> the fifth value type
+ * @param <T6> the sixth value type
+ * @param <T7> the seventh value type
+ * @param <T8> the eighth value type
  * @param <R> the result type
  */
 public interface Function8<T1, T2, T3, T4, T5, T6, T7, T8, R> {
diff --git a/src/main/java/io/reactivex/functions/Function9.java b/src/main/java/io/reactivex/functions/Function9.java
index 29c5605b74..11e7926c5c 100644
--- a/src/main/java/io/reactivex/functions/Function9.java
+++ b/src/main/java/io/reactivex/functions/Function9.java
@@ -19,13 +19,13 @@
  * A functional interface (callback) that computes a value based on multiple input values.
  * @param <T1> the first value type
  * @param <T2> the second value type
- * @param <T3> the second value type
- * @param <T4> the second value type
- * @param <T5> the second value type
- * @param <T6> the second value type
- * @param <T7> the second value type
- * @param <T8> the second value type
- * @param <T9> the second value type
+ * @param <T3> the third value type
+ * @param <T4> the fourth value type
+ * @param <T5> the fifth value type
+ * @param <T6> the sixth value type
+ * @param <T7> the seventh value type
+ * @param <T8> the eighth value type
+ * @param <T9> the ninth value type
  * @param <R> the result type
  */
 public interface Function9<T1, T2, T3, T4, T5, T6, T7, T8, T9, R> {