Someone who's oscitant is visibly bored and distracted. A classroom full of oscitant students can be extremely discouraging to a brand new teacher.
When someone isn't paying attention to you — yawning while you speak, watching the clock, or sighing deeply — you can describe them as oscitant. It's a useful adjective, but a very rare one — you're more likely to read it in an old book than to actually hear someone use it. Oscitant comes from the Latin word oscitans, "sluggish or lazy," which stems from oscitare, "to yawn," and os citare, "to move the mouth."