1. protected, sound, guarded. Safe, secure may both imply that something can be regarded as free from danger. These words are frequently interchangeable. Safe, however, is applied rather to a person or thing that is out of or has passed beyond the reach of danger: The ship is safe in port. Secure is applied to that about which there is no need to fear or worry: to feel secure about the future; The foundation of the house does not seem very secure. 4. sure, reliable. 5. wary, careful. 8. strongbox, coffer, chest, safe-deposit box.