What ground spices means
Ground spices are spices that have been dried and ground into a fine powder. They are made from many different parts of plants, including seeds such as cumin, coriander, fennel and mustard; bark such as cinnamon; roots and rhizomes such as ginger and turmeric; berries such as allspice and black pepper; flower buds such as cloves; pods such as cardamom; and fruits such as paprika and chilli. Ground spices are convenient, because they blend quickly and evenly into dishes, sauces, rubs, batters and doughs, and their flavour is released straight away. This makes them ideal for baking, where spices need to be spread evenly through cakes and biscuits, and for curries, stews, marinades and spice rubs.
Many spice blends, such as garam masala, curry powder, mixed spice and ras el hanout, are made from ground spices. However, after spices are ground, their essential oils start to evaporate, so they lose flavour and aroma more quickly than whole spices. For this reason, many cooks buy whole spices and toast and grind them as needed, using a spice grinder or pestle and mortar, which gives a fresher, more intense flavour. Ground spices are best bought in small amounts and stored in sealed jars away from light and heat.
In cooking, they are often fried briefly in oil to bring out their flavour, but they burn easily, so they need watching. You will see ground spices in recipes of every kind.