noun, na-adjective
reverse; inversion; upside down
Describes something being the opposite way around, inverted, or turned upside down. Can be used literally or figuratively.
その絵は逆しまに掛けてあった。
The picture was hung upside down.
彼の言うことはいつも逆しまだ。
What he says is always the reverse of the truth.
noun, na-adjective
Used for ideas, arguments, or situations that are contrary to reason or common sense. Often implies a perverse or twisted logic.
そんな逆しまな理屈は通らない。
Such absurd reasoning won't hold water.
逆 is the most common word for 'reverse' or 'opposite' and is used in many compounds. 逆しま is less frequent and carries a stronger nuance of being upside down or perversely wrong.
反対 means 'opposite' in a more neutral, positional sense. 逆しま often implies a more complete inversion or a morally wrong reversal.
The word さかしま is derived from 逆 (さか, 'reverse') + しま, an old suffix indicating direction or state. The kanji 逆しま is a standard spelling, while 倒 is a rare alternative.