diff --git a/poky/documentation/ref-manual/terms.rst b/poky/documentation/ref-manual/terms.rst
index cba514c..1e3f718 100644
--- a/poky/documentation/ref-manual/terms.rst
+++ b/poky/documentation/ref-manual/terms.rst
@@ -270,7 +270,7 @@
       your Linux distribution.
 
       Another point worth noting is that historically within the Yocto
-      Project, recipes were referred to as packages - thus, the existence
+      Project, recipes were referred to as packages --- thus, the existence
       of several BitBake variables that are seemingly mis-named, (e.g.
       :term:`PR`, :term:`PV`, and
       :term:`PE`).
@@ -369,7 +369,7 @@
      Directory created by unpacking a released tarball as compared to
      cloning ``git://git.yoctoproject.org/poky``. When you unpack a
      tarball, you have an exact copy of the files based on the time of
-     release - a fixed release point. Any changes you make to your local
+     release --- a fixed release point. Any changes you make to your local
      files in the Source Directory are on top of the release and will
      remain local only. On the other hand, when you clone the ``poky`` Git
      repository, you have an active development repository with access to
@@ -383,6 +383,31 @@
      ":ref:`overview-manual/development-environment:repositories, tags, and branches`"
      section in the Yocto Project Overview and Concepts Manual.
 
+   :term:`Sysroot`
+      When cross-compiling, the target file system may be differently laid
+      out and contain different things compared to the host system. The concept
+      of a *sysroot* is directory which looks like the target filesystem and
+      can be used to cross-compile against.
+
+      In the context of cross-compiling toolchains, a *sysroot*
+      typically contains C library and kernel headers, plus the
+      compiled binaries for the C library. A *multilib toolchain*
+      can contain multiple variants of the C library binaries,
+      each compiled for a target instruction set (such as ``armv5``,
+      ``armv7`` and ``armv8``), and possibly optimized for a specific CPU core.
+
+      In the more specific context of the OpenEmbedded build System and
+      of the Yocto Project, each recipe has two sysroots:
+
+      -  A *target sysroot* contains all the **target** libraries and headers
+         needed to build the recipe.
+
+      -  A *native sysroot* contains all the **host** files and executables
+         needed to build the recipe.
+
+      See the :term:`SYSROOT_* <SYSROOT_DESTDIR>` variables controlling
+      how sysroots are created and stored.
+
    :term:`Task`
       A per-recipe unit of execution for BitBake (e.g.
       :ref:`ref-tasks-compile`,