diff --git a/array.c b/array.c
index a2cf86a24c..3daed9984b 100644
--- a/array.c
+++ b/array.c
@@ -2819,7 +2819,7 @@ flatten(VALUE ary, int level, int *modified)
  *  Flattens _self_ in place.
  *  Returns <code>nil</code> if no modifications were made (i.e.,
  *  <i>array</i> contains no subarrays.)  If the optional <i>level</i>
- *  argument determins the level of recursion to flatten.
+ *  argument determines the level of recursion to flatten.
  *     
  *     a = [ 1, 2, [3, [4, 5] ] ]
  *     a.flatten!   #=> [1, 2, 3, 4, 5]
@@ -2854,7 +2854,7 @@ rb_ary_flatten_bang(int argc, VALUE *argv, VALUE ary)
  *  Returns a new array that is a one-dimensional flattening of this
  *  array (recursively). That is, for every element that is an array,
  *  extract its elements into the new array.  If the optional
- *  <i>level</i> argument determins the level of recursion to flatten.
+ *  <i>level</i> argument determines the level of recursion to flatten.
  *     
  *     s = [ 1, 2, 3 ]           #=> [1, 2, 3]
  *     t = [ 4, 5, 6, [7, 8] ]   #=> [4, 5, 6, [7, 8]]
diff --git a/bignum.c b/bignum.c
index 490944aa76..160e0f0f6a 100644
--- a/bignum.c
+++ b/bignum.c
@@ -470,7 +470,7 @@ rb_cstr_to_inum(const char *str, int base, int badcheck)
 	}
 	break;
     }
-    if (*str == '0') {		/* squeeze preceeding 0s */
+    if (*str == '0') {		/* squeeze preceding 0s */
 	while (*++str == '0');
 	if (!(c = *str) || ISSPACE(c)) --str;
     }
diff --git a/dir.c b/dir.c
index 8163a639de..bb5e9457a3 100644
--- a/dir.c
+++ b/dir.c
@@ -1035,7 +1035,7 @@ find_dirsep(const char *s, int flags)
     return (char *)p-1;
 }
 
-/* Remove escaping baskclashes */
+/* Remove escaping backslashes */
 static void
 remove_backslashes(char *p)
 {
diff --git a/enum.c b/enum.c
index 4e3ff927da..7a88b06988 100644
--- a/enum.c
+++ b/enum.c
@@ -1112,8 +1112,8 @@ minmax_ii(VALUE i, VALUE *memo)
  *     enum.minmax                   => [min,max]
  *     enum.minmax {|a,b| block }    => [min,max]
  *  
- *  Returns two elements array which contains the mininum and the
- *  maxinum value in the enumerable.  The first form assumes all
+ *  Returns two elements array which contains the minimum and the
+ *  maximum value in the enumerable.  The first form assumes all
  *  objects implement <code>Comparable</code>; the second uses the
  *  block to return <em>a <=> b</em>.
  *     
@@ -1255,7 +1255,7 @@ minmax_by_i(VALUE i, VALUE *memo, int argc, VALUE *argv)
  *     enum.minmax_by {| obj| block }   => [min, max]
  *  
  *  Returns two elements array array containing the objects in
- *  <i>enum</i> that gives the minmum and maximum values respectively
+ *  <i>enum</i> that gives the minimum and maximum values respectively
  *  from the given block.
  *     
  *     a = %w(albatross dog horse)
diff --git a/error.c b/error.c
index 25ddb344a0..5b60494275 100644
--- a/error.c
+++ b/error.c
@@ -667,7 +667,7 @@ name_err_name(VALUE self)
  * call-seq:
  *  name_error.to_s   => string
  *
- * Produce a nicely-formated string representing the +NameError+.
+ * Produce a nicely-formatted string representing the +NameError+.
  */
 
 static VALUE
@@ -993,7 +993,7 @@ errno_missing(VALUE self, VALUE id)
 }
 
 /*
- *  Descendents of class <code>Exception</code> are used to communicate
+ *  Descendants of class <code>Exception</code> are used to communicate
  *  between <code>raise</code> methods and <code>rescue</code>
  *  statements in <code>begin/end</code> blocks. <code>Exception</code>
  *  objects carry information about the exception---its type (the
diff --git a/hash.c b/hash.c
index 56b2bef935..bd22fef1da 100644
--- a/hash.c
+++ b/hash.c
@@ -1536,7 +1536,7 @@ rb_hash_update_block_i(VALUE key, VALUE value, VALUE hash)
  *  Adds the contents of <i>other_hash</i> to <i>hsh</i>.  If no
  *  block is specified entries with duplicate keys are overwritten
  *  with the values from <i>other_hash</i>, otherwise the value
- *  of each duplicate key is detemined by calling the block with
+ *  of each duplicate key is determined by calling the block with
  *  the key, its value in <i>hsh</i> and its value in <i>other_hash</i>.
  *
  *     h1 = { "a" => 100, "b" => 200 }
@@ -1661,7 +1661,7 @@ rb_hash_rassoc(VALUE hash, VALUE obj)
  *  hash. That is, for every key or value that is an array, extract
  *  its elements into the new array.  Unlike Array#flatten, this
  *  method does not flatten recursively by default.  If the optional
- *  <i>level</i> argument determins the level of recursion to flatten.
+ *  <i>level</i> argument determines the level of recursion to flatten.
  *
  *     a =  {1=> "one", 2 => [2,"two"], 3 => "three"}
  *     a.flatten    # => [1, "one", 2, [2, "two"], 3, "three"]
diff --git a/numeric.c b/numeric.c
index b9f2b1d084..e9ebd33202 100644
--- a/numeric.c
+++ b/numeric.c
@@ -2549,7 +2549,7 @@ fix_lt(VALUE x, VALUE y)
  *   fix <= other     => true or false
  *
  * Returns <code>true</code> if the value of <code>fix</code> is
- * less thanor equal to that of <code>other</code>.
+ * less than or equal to that of <code>other</code>.
  */
 
 static VALUE