Common names vary considerably but botanical names do not.
The Linaean system of classification is used uniformly all over the world. The common names of plants are not. When we use only the common name, there is much room for misunderstanding and error. For example, there are many plants that are referred to as "honeysuckle." Honeysuckle is actually a family of plants (Caprifoliaceae). To specify the exact plant, we must designate the genus and species. As another example, if I speak of the herb Noni, or Morinda. You wouldn't know if I meant Morinda citrifolia or Morinda officinalis, both of which are used by herbalists.
The English language contains many words from Latin. As a result, some of the Latin names will look familiar, and a few will be quite recognizable. For example, the English word "foliage" comes from the Latin, folium, meaning "leaf." When we see the botanical name for red clover, Trifolium pratense, it will not be hard to figure out that this is a three-leafed plant. Likewise for Morinda citrifolia, whose name means "citrus leaved."
It is beyond the scope of this lesson to cover all the Latin used in the taxonomic naming of herbs. However, we will find it beneficial to consider some of the more common names. One word that you will often see in the species name is officinalis. Some examples are:
Althaea officinalis (marshmallow)
Calendula officinalis (garden marigold)
Euphrasia officinalis (eyebright)
Morinda officinalis (Morinda or noni)
Smilax officinalis (sarsaparilla)
Taraxacum officinalis (dandelion)
Valeriana officinalis (valerian)
The Latin word officinalis means "of a storeroom" and is related to our words "office" and "official." It conjures up images of a storeroom where herbalists stored their herbs. "Officinal" herbs were "authorized herbs" so to speak, or herbs "officially recognized" for their medical use. Today, the word simply means "medicinal." When this appears in a botanical name, you know that the herb has a long history of medicinal use.
The Latin annuum, meaning "annual" (living only one year, or one plant season) also appears commonly in botanical names. An example is Capsicum (Capsicum annuum).
Sometimes the botanical name indicates where the plant originates from. For example, the botanical name for gotu kola, Hydrocotyle asiatica, indicates that the herb originates from the continent of Asia. Golden seal (Hydrastis canadensis) and blood root (Sanguinaria canadensis) are both found in Canada.
Where does the herb pygeum (Prunus africana) come from?