Tetris Glossary
Every Tetris mode leans on the same compact vocabulary: the well, a tetromino, a line clear, a T-spin. Once those words click, the rules for any version of the game read like plain English, and strategy guides stop sounding like a foreign language. This glossary gathers the terms you will meet across the whole site, from the absolute basics to the finer points of finesse and 20G play.
You do not need to memorize any of it. Skim the page to get a feel for the words, then dive into a game and come back whenever a term trips you up. Every entry has its own anchor, so the rules hub and the FAQ can point you straight to a definition. If you are brand new, read the first group, then pick up the rest as you go.
💡 Learn these four first: the well, the tetromino, the line clear and the hard drop. Almost every rule you read is built from those four ideas.
The board and the pieces
Tetromino
Any of the seven shapes made of four squares joined edge to edge. Tetris uses exactly seven of them - I, O, T, S, Z, J and L - each with its own name and color, and the entire game is the art of fitting them together.
Well (matrix)
The tall rectangular playfield where pieces fall and rows are cleared, also called the matrix. The standard well is ten cells wide and twenty tall. Big mode uses a smaller, chunky grid, while every other mode keeps the ten-by-twenty shape.
Cell (block)
A single square of the grid. Each tetromino fills four cells, and a row clears only when all ten of its cells are filled at once with no gaps left.
Spawn
The moment a fresh piece appears at the top of the well, ready for you to steer. If the stack has grown so high that a new piece has no room to appear, the game tops out.
Ghost piece
The faint outline projected onto the stack that shows exactly where the current piece will land if you drop it straight down. It removes the guesswork from lining up a placement and is a beginner's best friend.
Moving and placing a piece
Rotation
Turning a piece ninety degrees to fit a gap. Modern Tetris rotates around a fixed system, so the same input always produces the same spin, which lets you plan placements well in advance.
SRS (Super Rotation System)
The standard modern rotation system that defines how each piece turns and how it kicks off walls and floors. SRS is what makes advanced moves like T-spins possible and consistent across every guideline game.
Wall kick
When a rotation would overlap a wall or another block, the game nudges the piece sideways or up to a nearby legal spot instead of failing the spin. Wall kicks let you twist pieces into tight notches you could never reach by dropping.
Hard drop
Slamming a piece straight to the bottom of the stack so it locks instantly. Hard drop is the fastest way to place a piece and is essential in timed modes, though retro Classic mode leaves it out.
Soft drop
Speeding a piece downward without locking it immediately, so you can still nudge it sideways as it falls. Soft drop trades a little control for a little time and is the only speed-up available in Classic play.
Lock delay
The brief pause between a piece touching down and locking into the stack. That small window lets you make last-instant slides and rotations, which is how you tuck pieces neatly under overhangs.
DAS (Delayed Auto Shift)
The short delay before a held direction begins auto-repeating, sliding the piece continuously toward a wall. Tuning DAS lets you move a piece fully across the well in one motion instead of tapping repeatedly.
ARR (Auto Repeat Rate)
How fast a piece keeps moving once DAS kicks in and auto-shift begins. A faster ARR slides pieces across the board almost instantly, which speed players tune carefully alongside their DAS.
Finesse
Placing each piece using the fewest possible button presses. Because every wasted input costs time, mastering optimal finesse is the single biggest speed gain in Sprint and the other timed modes.
Hold
A side box where you can park one piece to save it for later, swapping it back in when you need it. Hold is a core planning tool for banking I-pieces and getting rid of awkward S and Z shapes. Classic mode has no hold.
Next queue
The preview strip showing the pieces still to come. Reading several pieces ahead lets you plan placements before they arrive, which is the difference between reacting to the board and controlling it.
Clears, scoring and speed
Line clear
The removal of a row once all ten of its cells are filled. Everything above a cleared row drops down to take its place, and clearing lines is the only way to keep the stack from topping out.
Single, double and triple
Clearing one, two or three rows with a single piece. Bigger clears score more per row, so a double beats two singles and a triple beats a double, which rewards patient stacking over clearing one line at a time.
Tetris (the clear)
Clearing four rows at once with a vertical I-piece dropped into a full-height gap. It is the highest-scoring basic clear and the move the game is named after, and chaining Tetrises is the backbone of every big score.
T-spin
Rotating a T-piece into a notch it could not slide into, clearing lines for far more points than a normal clear of the same size. You set one up by building an overhang with a T-shaped gap, then twisting the T in at the last instant.
Back-to-back
A bonus for chaining difficult clears - Tetrises and T-spins - without a plain single, double or triple breaking the streak. Keeping a back-to-back chain alive is where the biggest Ultra and Marathon scores come from.
Combo
Clearing at least one line with several consecutive pieces, never leaving a gap where a piece fails to clear. Each linked clear raises a combo counter that adds to your score, and Cascade mode is built entirely around long combos.
Perfect clear (all clear)
Emptying every cell of the well at once so no blocks remain at all. A perfect clear is one of the largest point bonuses in the game and a favorite thing to practice in the no-fail Zen mode.
Level
A number that rises as you clear lines and drives how fast pieces fall and how much each clear scores. In Marathon the level climbs one notch every ten lines; in Classic it feeds a famously steep scoring curve.
Gravity
The speed at which a piece falls on its own. Gravity increases with the level in most modes, turning a gentle warm-up into a scramble, until at its extreme it becomes instant.
20G gravity
Gravity so fast that a piece falls the full height of the well in a single frame, arriving already resting on the stack. There is no falling phase to steer, so 20G play is all about surface slides and rotation. It is the defining feature of Master mode.
PPS (pieces per second)
A measure of raw placement speed, counting how many tetrominoes you lock into the stack each second. Elite Sprint players sustain several pieces per second while keeping their finesse perfectly clean.
Garbage and digging
Garbage
Junk rows of blocks with a single gap that appear at the bottom of the well, either pushed up by the game or sent by an opponent in versus play. You clear garbage by filling that gap to complete the row.
Cheese
Garbage rows whose single holes are scattered from column to column so they never line up, resembling a block of cheese full of holes. Cheese mode is a timed race to dig through a wall of them.
Downstack
Clearing away existing rows to bring the stack height down, especially digging garbage out from the bottom. Downstacking is the survival half of Tetris, the counterweight to building new lines up top.
Upstack
Building the stack upward by placing pieces to set up big clears, the opposite of downstacking. Strong play balances patient upstacking with quick downstacking whenever the board gets dangerously tall.
Top-out
The end of a game, when the stack reaches the top of the well and a new piece has no room to spawn. Every survival mode is really a fight to hold off the top-out for as long as you can. Zen removes it entirely.
Retro techniques and culture
Seven-bag randomizer
The piece-selection system that shuffles all seven tetrominoes into a bag and deals them out one at a time before refilling, so each piece appears once per bag. It guarantees a fair spread and lets you count pieces ahead. Classic mode uses an older, more random method instead.
Kill screen
The point in retro Classic Tetris, famously level 29 on the NES, where gravity becomes so fast that normal play breaks down. Once treated as a hard wall, it is now pushed past with advanced tapping techniques.
Hypertapping
Vibrating your thumb to press the direction button many times per second, moving pieces sideways faster than simply holding it would at high speed. It was the first technique to carry players past the Classic kill screen.
Rolling
A newer Classic technique where you drum your fingers on the back of the controller to tap the pad far faster than hypertapping, pushing scores into the millions well beyond the old kill screen.
The Tetris effect
The tendency to picture falling blocks and imagine fitting them together after a long session, even with your eyes closed. It is a well-documented quirk of how the brain rehearses an absorbing visual task.
That is the working vocabulary of Tetris. Keep this page open in a tab the first few times you try a new mode and the words will stick fast. Ready to put them to use? Drop into a game of Marathon, read the full Tetris rules, or browse every mode on the site.