In printed circuit boards, Teardrops are typically drop-shaped features at the junction of vias (teardrop vias) or contact pads (teardrop pads) and traces (teardrop traces). While a typical shape of a teardrop is straight-line tapering, they may be concave. This type of teardrop is also called filleting or straight.

For more information, just jump to check the page of All about Teardrops in PCB Design | PCB and Assembly | MADPCB