Falling Blocks Glossary — 30 Terms Explained

Pieces and board

Board / playfield — the 10 × 20 grid where pieces fall.
Piece — a shape made of four blocks. There are seven: I, O, T, S, Z, J and L.
I-piece — the long bar of four; the only piece that can clear four lines at once.
Stack — the blocks that have already locked on the board.
Hole — an empty cell with a block above it.
Overhang — a block that sticks out over an empty cell, often used for T-spins.
Well — a single empty column kept open for an I-piece.
Garbage — messy, hole-filled rows near the bottom of the stack.

Rotation — turning a piece 90°. Tap the board in Drop Peak.
Wall kick — the game nudges a piece sideways or up so a rotation next to a wall or the stack succeeds.
Soft drop — making a piece fall faster while you keep control.
Hard drop — dropping a piece instantly to its landing spot.
Ghost piece — the outline that shows where the piece will land.
Hold — setting the current piece aside to use later, once per drop.
Preview / next queue — the upcoming pieces; Drop Peak shows three.
Lock delay — the short time a landed piece can still move before it locks (0.5 s, up to 15 resets).
Gravity — the speed pieces fall at; it rises with your level.

Line clear — removing a completely filled row.
Single, double, triple — clearing one, two or three lines with one piece.
Quad — clearing four lines with one I-piece; the biggest normal clear.
T-spin — rotating a T-piece into a tight slot as its final move; pays extra.
Back-to-back (B2B) — two difficult clears (quads or T-spins) in a row; ×1.5 bonus.
Combo — consecutive pieces that each clear a line; adds 50 × combo × level.
Level — rises every 12 lines in Drop Peak and multiplies your points.

7-bag — a randomizer that deals all seven pieces once per batch in a shuffled order. It prevents long droughts and floods.
Drought — a long wait for a piece, usually the I. The 7-bag caps it at 12 pieces.
Seed — the number that fixes a piece order. The Daily Challenge uses one seed for everyone.