The present study examines young children's uses of semantically specific and general relational containment terms (e.g. in, enter) in Hindi and Tzeltal, and the extent to which their usage patterns are influenced by input frequency. We hypothesize that if children have a preference for relational terms that are semantically specific, this will be reflected in early acquisition of more semantically specific expressions and underextension of semantically general ones, regardless of the distributional patterns of use of these terms in the input. Our findings however show a strong role for input frequency in guiding children's patterns of use of containment terms in the two languages. Yet language-specific lexicalization patterns play a role as well, since object-specific containment verbs are used as early as the semantically general 'enter' verb by children acquiring Tzeltal.