upside down; the wrong way up; back to front; the wrong way round; inside out
A picture hung upside down
He holds his book upside down/the wrong way up
To wear one's sweater back to front/the wrong way round
To wear one's sweater inside out
To put one's shoes on the wrong feet
against (the wind, the tide)
To swim against the current; To swim upstream
opposite; contrary
The opposite direction