This study explores the possibility of an experimental sociolinguistic approach to the social meaning indexed by grammatical and pragmatic features, like address terms and interrogative endings in Korean. That kind approach is inevitable because they have relatively infrequently occuring features and thus seems to resist well-known variationist approaches. The first experiment, to test that possibility, deals with Korean address terms with a situated discourse completion task. The task apparently asks for request acts, but it actually is designed for Korean address terms. The results show that power and imposition are signficant pragmatic features, but remoteness is not. The second experiment was designed to test for sociolinguistic factors relevant for choosing the interrogative endings -nay and -ni. The results show that factors of age group and relationship are significant, whereas the others are not.