Here's how you can tell Siri on your iPhone who's who in your life. This makes it easy for you to tell Siri to call or text that person by using a social term such as "call my husband" or "call my aunt."
1. Long press the Home button to call up Siri.
2. Tell Siri who the person is in your life, as per the examples below: "Robert is my husband" "Susan is my wife"
3. You will now be able to tell Siri "call my husband" or "text my wife."
For more, see the original article at the link below.
iPhone 5 Tips and Tricks | Apple