View the original community article here
Last tested: Sep 30, 2019
On Dashboard Next, when a dashboard is in edit mode, you can hide a title by clicking Hide title in the tile’s three-dot menu.
On Legacy Dashboards you can do this by clicking the eye icon next to the title of a tile while editing the dashboard.
But for single value vizualization tiles, you can only do this via the edit tab of the visualization - there's a "Show title" toggle.