'larval' originates from New Latin, specifically the word 'larva,' where 'larva' meant 'ghost, mask; the immature form of an insect.'

'larva' was adopted into English in the 18th century from New Latin, and the adjective form 'larval' was formed to describe things relating to a larva.

Initially, 'larva' meant 'ghost or mask' in Latin, but in scientific usage, it came to mean the immature stage of an insect, and 'larval' took on the meaning of 'relating to a larva.'