How would you describe spiciness to someone who has never tasted anything spicy in life?

There's a lot to unpack with this question. Wasabi and horseradish can make your sinuses and nasal passages burn. In high quantities, it can do the same with your mouth, but less so. There is flavor to these things to. Both have earthy flavors.

If you are talking chillies, then the heat burns on your tongue and lips, but not in your sinuses. These can have a sweet and fruity background flavor. This sweetness can be enhanced by roasting. Roasting can also give flavors consistent with other roasted things. Smoky, meaty, etc. The fullness of these flavors are collectively referred to as the Mailard reaction. Other flavors can be added by smoking the chilies.

Yum!

I would say that you tell them the spiciness of something would be like getting close to a fire. The closer you are the hotter the spice would feel inside your mouth

very flavorful and sometimes warm/hot/fiery

There are so many types of hot spices that I couldn't possibly describe all the ones that just I only know!

Some might describe one well, not knowing of others. And a expert might describe many, yet not have had the same one as the first.

alive . vibrant .

A sharpness or burning sensation in your mouth.

Warm and tingly, full of flavor

I might make ur mouth burn!

Let them taste differentspices