diff --git a/README.md b/README.md
index c19baae..7cce8bc 100644
--- a/README.md
+++ b/README.md
@@ -84,7 +84,7 @@ With the mapping, you can align selected lines of text with only a few keystroke
 
 1. `<Enter>` key to start interactive EasyAlign command
 1. Optional Enter keys to select alignment mode (left, right, or center)
-1. Optional field number (default: 1)
+1. Optional field index (default: 1)
     - `1`         Around the 1st occurrences of delimiters
     - `2`         Around the 2nd occurrences of delimiters
     - ...
@@ -247,7 +247,7 @@ my_hash = { :a   => 1,
 ```
 
 However, in this case, we don't really need blockwise visual mode
-since the same can be easily done using the negative field number: `<Enter>-=`
+since the same can be easily done using the negative field index: `<Enter>-=`
 
 Alignment options
 -----------------
@@ -508,7 +508,7 @@ let g:easy_align_bang_interactive_modes = ['c', 'r']
 
 ### Alignments over multiple occurrences of delimiters
 
-As stated above, "field number" is used to target specific occurrences of
+As stated above, "field index" is used to target specific occurrences of
 the delimiter when it appears multiple times in each line.
 
 To recap:
diff --git a/doc/easy_align.txt b/doc/easy_align.txt
index 139ae2f..428fb02 100644
--- a/doc/easy_align.txt
+++ b/doc/easy_align.txt
@@ -36,7 +36,7 @@ With this mapping, you can align selected lines of text with a few keystrokes.
 
 1. <Enter> key to start interactive EasyAlign command
 2. Optional Enter keys to select alignment mode (left, right, or center)
-3. Optional field number (default: 1)
+3. Optional field index (default: 1)
     1        Around the 1st occurrences of delimiters
     2        Around the 2nd occurrences of delimiters
     *        Around all occurrences of delimiters
@@ -175,7 +175,7 @@ Available options are as follows.
 |                  |                  |   (right, left, center)       |
 | indentation      | string           | 'k'                           |
 |                  |                  |   (keep, shallow, deep, none) |
-| mode_sequence    | string           | (Depends on field number and  |
+| mode_sequence    | string           | (Depends on field index and   |
 |                  |                  |  selected alignment mode)     |
 
 There are 4 ways to set alignment options (from lowest precedence to highest):
@@ -407,7 +407,7 @@ settings as follows.
 Alignments over multiple occurrences of delimiters
 -------------------------------------------------------------------------
 
-As stated above, "field number" is used to target specific occurrences of
+As stated above, "field index" is used to target specific occurrences of
 the delimiter when it appears multiple times in each line.
 
 To recap: