A nut butter is a type of spread. It is made by grinding dry roasted nuts until the fat separates. Different nut butters have different textures and flavours. The most commonly known nut butter in the United States is peanut butter.
Any nut can be used to make a nut butter. Here are some examples:
Some seeds with enough fat (e.g. from sunflowers, sesame, and pumpkins) are also used to make something similar.