noun
undefeated record; clean record; no losses
Sumo term for a wrestler who has not yet lost a bout in a tournament; literally 'without touching the dirt'.
彼は初日から土付かずで勝ち進んでいる。
He has been winning without a loss since the first day.
土付かずの力士が優勝争いをリードして
The undefeated wrestler is leading the championship race.
全勝 means winning all matches, often used in sports generally; 土付かず is specifically a sumo term emphasizing an unblemished record.
無敗 is a general term for 'undefeated' in any competition; 土付かず is a sumo-specific expression.
From 土 (つち, 'earth' or 'dirt' of the sumo ring) + 付かず (negative form of 付く, 'to touch'), literally 'without touching the dirt', referring to a wrestler who has not been thrown to the ground.