どっち
どっち · docchi · JLPT N5 · noun
one
docchi = casual どちら: do (which) + chi (direction)
Short form of どちら (dochira). The do- marks a question, as in どこ (where) and どれ (which); -chi means direction or side, as in こっち (this way) and そっち (that way). So どっち asks which side: which of two, or which way.