How does a word become a curse?

A Word can become a curse depending on how that Word or phrase is used. For example, if you were to say 'i dislike you', you could mean it in a jokey sort of way, or in a rude, harsh way. Also, certain Words have specific letters in that make the Word sound mean. Like if someone said a Word like 'squishy' or 'silly' you would feel happy and jokey with them. But if the person used a Word with harsh syllables, like 'hate' or 'stink', you could feel as though the other person is being mean etc to you.