رضا: You guys obviously aren't from Southern California and the land of freeways, cars, and traffic! :)
It's a trip to work. There are statistics that call them trips or cartrips.

Going to work can be a journey or a voyage or often times an adventure. It is quite common for people to drive over 50 miles one way to get to work. I used to work in downtown Los Angeles and it is 34 miles one way from here. "Good morning commuters, there's big rig jackknifed on the 405 at Imperial and it's caused a Sigalert, you'd better use an alternate route. Let's talk to Jeff in the 'copter over the six car pile up at the 605 and 91." And when it rains around here, it's a real mess. Good thing it doesn't snow. At least twenty radio stations will broadcast traffic conditions throughout the day. Two of them, KNX 1070 and KFW 980, do it every six to ten minutes. We have a lot of television stations do it too.

Drive is the other word that would be used.

For sentence 1, I'd use "trip" from your list, but it'd be common to hear "drive" or "commute" around here.

For sentence 2, I'd use "trip" from your list. Vacation would be common and if by ship you'd hear cruise. Canadians use the word "holiday" as Americans use the word "vacation."

Because of the word "day" in front of your blank in sentence 3, about the only word I would use is "trip." A day trip is a common expression for a trip that has you returning to the starting point the same day. It's said of hiking too.

For sentence 4 from your list, "excursion" might be used. I wouldn't use outing for part of a paid and organized trip. Outing to me is something spontaneous that a family might do, like jump in the car and just head off until something comes up or maybe just head to the beach to spend the day and walk around. I've seen another word for this in travel brochures, but it escapes me right now. It could also be called a "side trip", but I doubt if they'd word it that way in an advertisement. "Tour" is the word I'm thinking of. A full day tour or guided tour.

Sentence 5. Trip or journey seem OK to me. Journey usually implies having to make extra effort to get to somewhere, and the Himalayas qualify.
_________ _________ __________ _________ _______

Voyage doesn't have to be by ship or even a trip to anywhere. It is sometimes said when one is going through life that you're on a voyage. Or a voyage of time. It can also be used for a land crossing, but it's not a very commonly used word. It is as you say much more common for use with travelling by water, but also some type of conveyance. So a train trip could be a voyage across a continent or said of a covered wagon from the pioneer days to cross the continent.

Excursion is not word too many people use. Now that Ford has made this giant SUV and named it the "Excursion" I only hear it when someone is talking about those. The word has a thrusting connotation to it to me and I think of military terminology when I hear it. I suppose it can used to describe some types of trips or vacations.