Tree Pattern Baldness. It's like male pattern baldness, but it's only temporary and it happens once a year.
Why do we say a "pair" of pants?
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It is easy to go down into Hell;
Night and day, the gates of dark Death stand wide;
But to climb back again, to retrace one's steps to the upper air –
There's the rub, the task.
– Virgil, The Aeneid (Book VI)