Here are some plant terms & definitions that may help you understand what you are reading at various places.
Annual - Completes life cycle in a single year Biennial - Completes life cycle in two years; the first year typically as a rosette and the second year it flowers Perennial - Lives more than two seasons. Evergreen - Keeps its leaves year round. Deciduous - Looses its leaves at the end of the growing season.
Root Types
Tap - It has one main root Fibrous - It has many equal roots, ie no dominant roots. Adventitious - This is a root that develops from a part of the plant other than another root, like the prop roots of maize or the runners of a cobra. Root Hairs - These are the tiny outgrowths of the epidermis designed to absorb water and minerals.
Stem Terminology
Node - Area where the leaf is attached to the stem. Internode - Area between nodes. Bud - These are found at the base of leaves and are immature shoot systems. Axillary bud - These are found at the base of leaves along the stem. These are what grow when you do a Nemesis cutting. Terminal Bud - This is the bud at the end of a stem. Bud Scales - Modified leaves creating a protective covering over the bud. Bud Scale Scar - This a the scar left on a stem where the terminal bud scales fell off. Leaf Scar - This is the scar left on the stem after a leaf has been detached. Lenticel - This is areas on the stem for gas exchange.
Leaf Parts
Tentacle - This is the little hair like bristles that cover sundew leaves/pads and holds a single drop of dew perched atop it. Blade - This is the main photosynthetic part. Petiole - This is simply the leaf stalk. Stipules - This is the appendage at the base of the petiole in some leaves, completely lacking in many plants.
Meristems - Growth in plants is restricted to certain regions called meristems. These can be found at the tips of roots and stems and are responsible for growth in length.
Misc
Rhizome - Central bulb like growth that produces leaves and roots, such as sarracenia and flytraps. Media - We call what we grow cp's in media rather than dirt. Dirt has nutrients, nutrients kill cp's. So we use media to avoid confusion. CP - Carnivorous Plants
Here are some diagrams I have found from various places that show the different plant parts. None of the following images belong to me. Click on the names to see the diagrams.