desert =  (noun) A desert is a barren area of landscape where little rain occurs and consequently living conditions are hostile for plant and animal life.

• Arabian desert, Sahara desert, Thar desert etc.

dessert  = (noun) course of fruit etc. at the end of a meal.

• We had ice-cream for dessert.
• They had arranged a large choice of desserts at the wedding party.

desert = ( verb)  1. go away from

• The streets were deserted on the day of harthal.

desert= (verb )  2.  leave without help or support, especially in a cruel way.

• He deserted his ailing parents and went after his hobbies with friends

deserts = (noun, plural) what somebody deserves, if bad.

• You will be punished according to your deserts.
• A time will come when you’ll have to meet with your deserts.