取代 means 'to replace, supplant' and emphasizes that one thing completely takes the place of another, often permanently or in a systemic way (e.g., a new system replacing an old one). It is more formal and forceful than 替 or 代替, which are everyday words for substituting one person or thing for another. 更换 is specifically for replacing a worn-out item or changing details like an address, while 接替 is for taking over a role or position.