Answer:

doodlebug

Answer	Crossword Clue
DOODLEBUG	Divining rod
DOODLEBUG	Insect larva
DOODLEBUG	Robot bomb.

DOODLEBUG	Rube Goldberg gadget.
DOODLEBUG	Small "drone" plane.
DOODLEBUG	Rail-maintenance car

Crossword

a puzzle consisting of a grid of squares and blanks into which words crossing vertically and horizontally are written according to clues.