The following is a growing list of vocabulary that I have gained and sometimes use on my blog. The definitions are my own words which may or may not be similar to a dictionary definition. Many of the words refer to classifying or naming plants. Others are used to describe the appearance or growing nature of the plant. [Note: There is an emphasis on vocabulary that specifically pertains to Aroids, since that is my area of highest interest.]
epiphyte – a plant that grows attached to a host plant (usually a tree). The host plant is only used for anchorage, while the epiphytic plant receives its moisture and nutrients from the air. Examples include many Orchids and Aroids.
hemiepiphyte – a plant that can transition from being soil-based to tree-based (epiphytic) or vice versa. Usually this refers to a plant that begins it’s life in a tree, but sends roots to the ground below. A primary example is the group of strangler Figs.
heteroblastic -quality that describes plants with significantly different juvenile and mature stages. For example, leaves can develop splits or fenestrations as the plant climbs a tree and matures.
intergeneric – a hybrid plant made by crossing two plants from different genera. This is fairly common in the Orchidaceae family, but not as common in other plant families. The resulting plant is usually given a new genus name that is a combination of the two parent genera. (i.e. The hybrid orchid genus Miltassia is a cross of plants from the natural genera Miltonia and Brassia) It is even possible to cross more than two genera to create a new hybrid genus. (i.e. Iwanagara is a cross of Brassavola, Cattleya, Diacrium and Laelia)
self-heading – a plant which forms a large, stiff stim which is strong enough to support the plant in upward growth for a time. This term is usually used in reference to plants from the genus Philodendron, in contrast to the vining species of Philodendron.
There is a decent botanical glossary here.