processionary
Pronunciation: /prəˈsɛʃ(ə)n(ə)ri/
noun
(also processionary moth)- a greyish moth whose caterpillars live communally in silken tents in trees, marching out at night in procession to feed, causing substantial damage.
- Family Thaumetopoeidae: several species, in particular the European pine processionary (Thaumetopoea pityocampa)
- (also processionary caterpillar) the larva of the processionary moth.