Slow fade is gradually reducing contact with someone you are dating instead of ending things directly. Less brutal than ghosting but still avoidant. Not concerning, just dating vocabulary; worth conversations about honest communication. If your kid uses it constantly, ask them where they first heard it, not to police their speech but to understand which online community they are in. Most slang of this kind moves through TikTok and group chats, so seeing it in your child's vocabulary just means they are plugged into normal teen internet culture.