placoid /plakˈoid/

1. (of scales) plate-like
2. (of fish, eg sharks) having placoid scales, irregular plates of hard bone, not imbricated

• screw over
• screw-pile
• screw-piles
• screw pine
• screw pines
• screw plate
• screw plates
• screw press
• screw presses
• screw propeller
• screw-propeller
• screw propellers
• screws
• screw steamer
• screw steamers
• screw tap
• screw taps
• screw them
• screw thread
• screw threads
• screwtop
• screw-topped
• screwtops
• screw up
• screw-up