Used as a verb, you bump into something when you hit it, but not especially hard. You might bump your knee on your coffee table if you are walking around your living room in the dark. As a noun, a bump is a raised, slightly rounded area on something else. The stone pillar in the picture has a lot of bumps carved into it.
A clump is a group of similar things, very close together and hard to separate. The picture is of a clump of yellow flowers.
A hump is a large lump on the back of an animal or a person. On people, a hump is usually caused by your spine curving from old age. With animals like the camel in the picture, the hump is mostly fat, and it stores food.
This horse is jumping over the barrier. When you jump, your legs leave the ground and you either go up in the air or over something.
A lump can mean more than one thing. A lump can be a raised bump on something else. The person in the picture has some lumps on their arm. A lump is also a piece of something that has an irregular shape, such as a lump of coal.
A pump is a device used to move around fluids like water from place to place. Pumps are commonly used to get water out from below the ground. They can be hand driven, like the pump in the picture, wind driven, or driven by a motor.
An animal's rump is its fleshy hindquarters, bottom or buttocks. A cut of meat taken from an animal's rump may have the same name, for example rump steak.