Yōga Sūtra 1.08

विपर्ययो मिथ्याज्ञानमतद्रूपप्रतिष्ठम्।

viparyayō mithyājñānamatadrūpapratiṣṭham।

[विपर्ययो मिथ्याज्ञानम् अतद्रूप प्रतिष्ठम्।
viparyayō = misunderstanding or overthinking is; mithyājñānam = false knowledge; atadrūpa = form, which is not; pratiṣṭham = inferred by seeing;]

Viparyaya, i.e. misunderstanding or overthinking, is the incorrect knowledge inferred by seeing the form, which is not.

In a dull light, if you see a rope and conclude it as a snake, it is a misunderstanding. During eclipse, if you assume the sun is harmed, it is overthinking.