Lock away Definition 1 of 3Pro Tip 1/3Valuable Items Use 'lock away' for items worth protecting from theft or damage. After the show, he locked away his guitar. Pro Tip 2/3Safety Reason It's often used for putting dangerous items out of reach. The chemicals were locked away after class. Pro Tip 3/3Privacy Protection Can indicate hiding personal information or items from others. She locked away her diary.