Bit of gear for an entomologist

NET

Hint: This tool is often used to catch flying subjects of study. (This hint suggests the function of the item without naming it, guiding the solver toward the idea of capturing insects, which is a key use of a net in entomology.)

The clue "Bit of gear for an entomologist" leads to the answer "NET" through the following reasoning: An entomologist is a scientist who studies insects. A net is a common tool used by entomologists to catch insects for study. The word "gear" hints at equipment or tools, reinforcing that a net is a piece of equipment used in this field.