Special equipment: a well-seasoned ridged grill pan
Directions
Stir together lime juice, honey, oil, and coriander in a shallow dish. Add swordfish, turning to coat, and marinate at room temperature, turning over once, 15 minutes. (Do not marinate longer.)
Remove peel, including all white pith, from lime with a sharp paring knife. Cut segments free from membranes and finely chop segments, then combine with remaining salsa ingredients in a bowl.
Lightly brush grill pan with oil and heat over moderately high heat until just beginning to smoke. Remove swordfish from marinade and season both sides with salt and pepper. Grill fish until just cooked through, 3 to 4 minutes per side. Serve topped with salsa.