Virga

noun

1. A type of note used in plainsong notation, having a tail and representing a single tone.
2. A streak of rain or snow that is dissipated in falling and does not reach the ground, commonly appearing descending from a cloud layer.
3. (measurement) A unit of length: a rod, pole or perch (5½ yards); or a unit of area: a square rod, pole or perch.