When you spell a word, you write or speak each letter in the word in the correct order.

Someone who can spell knows the correct order of letters in words.

If something spells a particular result, often an unpleasant one, it suggests that this will be the result.

A spell of a particular type of weather or a particular activity is a short period of time during which this type of weather or activity occurs.

A spell is a situation in which events are controlled by a magical power.

If something or someone casts their spell on you or casts a spell on you, you are fascinated or charmed by them.

If you are under someone's spell, you are so fascinated by them that you cannot think about anything else.