To reawaken is to revive or to wake up again. A block party may be just the thing to reawaken your neighborhood's community spirit.
You'll almost always find reawaken used to talk about a state, emotion, or feeling, rather than a literal waking up from sleep. It's true, if you hit your alarm's snooze button, it will reawaken you in ten or fifteen minutes. But more often, you'll see your brother's interest in sports reawaken or your dad's sympathy for a cranky friend reawaken.