Portelude
(n.) The blank half-second at a door you have used a thousand times, in which you have no idea whether it pushes or pulls.
portelude (n.) — POR-tuh-lood. The small, humbling gap at a familiar door when your hand is already on it and your entire body has forgotten which way it opens.
From the Latin porta, a gate, and prelude, a thing that happens just before the real event. The word implies an audience. A portelude endured alone, in an empty corridor, barely counts; the true form requires at least one person behind you who has somewhere to be.
It is not a failure of memory so much as a failure of nerve. You know the answer. You have known it for years. But the hand hesitates, the door is briefly a stranger, and there follows the small indignity of the corrective shove — the push that becomes a pull halfway through, performed with a smile at nobody. Sign-makers have fought this for a century, which is why so many doors carry the words PUSH and PULL in a typeface chosen to be read at a glance, and why almost nobody has ever read one. The handle says more than the sign does, and a flat plate on the side that pushes is the only design that has ever really worked.
Usage: She had worked in the building for nine years and still suffered a portelude at the main entrance every single morning, which she had come to regard as the price of admission.