"Walk" is a nice, simple, basic word. It includes _every_ kind of locomotion on foot that's slower than a trot or a run. It could include ambling, strolling, marching, race-walking, etc. A "hike" usually means a vigorous recreational walk, often on a rough trail through countryside. It can also mean simply a long, vigorous walk. "Let's hike up Buck's Hill. It's an easy hike and there's a spectacular view at the summit." "A remark by President John F. Kennedy touched off an interest in fifty-mile hikes." "Join the Conservation Commission on a hiking tour of open space in our town. Be sure to bring sunblock, water, suitable shoes, and insect repellent."

The wing is the part of the bird. The action it makes when moving is flapping. Also, when someone is very anxious, and running around ineffectively, a phrase English (not American) people use is 'in a flap' i.e., they are behaving like a bird.