viparyayo mithya jnanam a tad rupa pratistham
विपर्ययो मिथ्याज्ञानमतद्रूप प्रतिष्ठम्

Misconception is mistaken perception of the true form

Yoga Sutras of Patanjali, 1.8

viparyayo = misconception
mithya = (is) mistaken
jnanam = knowledge
a tad rupa = not that form
pratistham = (of the true) form

I often mistake things for other things and it’s so weird when you actually see what you think is there until you realise what it really is. In this one he is freaked out when he thinks the rope is a snake, but then he finds out that it‘s just a rope and can bring him joy in the form of a swing 💖