short weight; weight shortage
Refers to a situation where the actual weight is less than the required or stated weight, often in commercial or shipping contexts.
This product was returned due to short weight.
noun which may take the genitive case particle 'no'
underweight
Describes something that is below the expected or standard weight, used as a noun or with の to modify another noun.
Underweight packages incur an additional charge.
Compound of 重量 (weight) and 不足 (shortage, insufficiency).