Tedashi and tsumogiri

Tedashi and tsumogiri are terms that describe where in the hand a tile was discarded:

• Tedashi means to discard a tile that was already in the hand, i.e. any tile other than the just-drawn tile.
• Tsumogiri means to discard the just-drawn tile.

Reading opponent's tedashi and tsumogiri discards can be useful, as they can indicate what shapes are likely/unlikely to be in their hand. They are typically combined with other discard reading strategies.

When playing with physical tiles, players will have to manually check for tedashi/tsumogiri. In online clients, it will vary. Notably, tenhou.net and Mahjong Soul have animations to display tedashi/tsumogiri when a tile is discarded, but do not indicate anything after the discard (forcing players to memorize the status of each desired tile).

Notes

• Beginners do not need to worry about tedashi/tsumogiri - other things like tile efficiency are far more important at this stage. Being able to build hands efficiently is required for discard reading.
• It is not required to memorize every single tile (e.g., if a guest wind is discarded turn 2, it doesn't matter if it's tedashi or tsumogiri). Try to focus on important tiles, such as dora and middle tiles.