Describes a situation, treatment, or judgment that is biased or incomplete, often implying unfairness. Commonly used in contexts like 片手落ちな態度 (a one-sided attitude) or 片手落ちの判断 (a partial judgment).
Listening only to his opinion is one-sided.
Please be careful not to make a partial evaluation.
Compound of 片手 (one hand) and 落ち (falling, omission), literally 'one hand missing'. The exact historical derivation is uncertain, but the word figuratively expresses incompleteness or bias.