Focused and capable at one’s task. Not distracted from performing perfectly. ‘Zone’ refers to total focus upon one’s action, such as a soccer player who doesn’t miss a goal kick or a baker producing hundreds of cookies, both are efficiently working with no distraction. (Compare to Draw a bead on or Zero in on; Opposite of Zoned-out.)

“In the accounting office, she’s in the zone doing all the profit & loss figures without fail.”