(Heb. gazam). The English word may denote either a caterpillar (as rendered by the LXX.), which wanders like a palmer or pilgrim, or which travels like pilgrims in bands (Joel 1:4; 2:25), the wingless locusts, or the migratory locust in its larva state.
These dictionary topics are from M.G. Easton M.A., D.D., Illustrated Bible Dictionary, Third Edition, published by Thomas Nelson, 1897. Public Domain, copy freely.
Easton, Matthew George. "Entry for 'Palmer-worm'". "Easton's Bible Dictionary".