What does this icon in Outlook 2013 mean?
<p>Does anyone know what this Outlook 2013 icon means? My Google skills are failing me this morning</p>

<p><a href="https://i.stack.imgur.com/t8urQ.png" rel="nofollow"><img src="https://i.stack.imgur.com/t8urQ.png" alt="enter image description here"></a></p>