preferably

British  

/ ˈprɛfrəblɪ, ˈprɛfərəblɪ /

adverb

1. ideally; by preference; if one had a choice

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Explanation

The adverb preferably refers to the most desirable choice. You could say you were looking for a new car, preferably a hybrid. That means that a hybrid is the kind of car you would choose over any other kind. As preferably is the adverb form of the word "prefer," we can find its roots in the Latin praeferre, which means "to set before." When you use preferably you're saying you'd set that choice before all others, though you might accept something else. Musician David Byrne once said, "I wanted to be a secret agent and an astronaut, preferably at the same time."