'Mō tóu' literally means 'to touch head' — combining the verb 摸 (mō, 'to touch, stroke, or pat') with the noun 头 (tóu, 'head'). It describes the gentle, affectionate act of patting or stroking someone’s (or something’s) head, usually to express comfort, reassurance, approval, or fondness. Unlike more formal or clinical terms, this phrase carries warmth and intimacy.

This expression is commonly used with children, pets, or close family members — for instance, a parent soothing a crying child or someone calming an anxious dog. While it can be used playfully among peers, it’s generally avoided in formal or professional settings, as it may imply condescension or overfamiliarity. The action is typically light and brief, not forceful or prolonged.