v.1. To enter something as data into a computer system or program using a keyboard; input something: I keyed the statistics in and analyzed the patterns. The researcher keyed in the results of the experiment and printed out a copy.
2. To become aware of or responsive to someone or something: If they are going to be good leaders, they need to key in to the needs of the voters. We stated our complaints very clearly, but the manager hasn't keyed in.
3. To cause someone to become aware of or responsive to someone or something: We don't know the strategy yet, but you can key us in. The manager keyed in the employees to the new dress code.