1. To observe carefully or inspect.
2. To question closely.

To query with the expectation of an immediate response. For example, a computer may interrogate an attached terminal to determine the terminal’s status (readiness to transmit or receive).
To pose a series of questions to; SYN. question.

1. To call into question; challenge the accuracy, probity, or propriety of; SYN. oppugn.
2. To pose a question; SYN. query.