diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst
index d54ecd75a2628f..428ce51165c9b5 100644
--- a/Doc/library/sys.rst
+++ b/Doc/library/sys.rst
@@ -604,12 +604,18 @@ always available.
    +---------------------+----------------+--------------------------------------------------+
    | :const:`radix`      | FLT_RADIX      | radix of exponent representation                 |
    +---------------------+----------------+--------------------------------------------------+
-   | :const:`rounds`     | FLT_ROUNDS     | integer constant representing the rounding mode  |
-   |                     |                | used for arithmetic operations.  This reflects   |
-   |                     |                | the value of the system FLT_ROUNDS macro at      |
-   |                     |                | interpreter startup time.  See section 5.2.4.2.2 |
-   |                     |                | of the C99 standard for an explanation of the    |
-   |                     |                | possible values and their meanings.              |
+   | :const:`rounds`     | FLT_ROUNDS     | integer representing the rounding mode for       |
+   |                     |                | floating-point arithmetic. This reflects the     |
+   |                     |                | value of the system FLT_ROUNDS macro at          |
+   |                     |                | interpreter startup time:                        |
+   |                     |                | ``-1`` indeterminable,                           |
+   |                     |                | ``0`` toward zero,                               |
+   |                     |                | ``1`` to nearest,                                |
+   |                     |                | ``2`` toward positive infinity,                  |
+   |                     |                | ``3`` toward negative infinity                   |
+   |                     |                |                                                  |
+   |                     |                | All other values for FLT_ROUNDS characterize     |
+   |                     |                | implementation-defined rounding behavior.        |
    +---------------------+----------------+--------------------------------------------------+
 
    The attribute :attr:`sys.float_info.dig` needs further explanation.  If