Term:

Carpel
Definition:

The fundamental unit of the gynoecium, often considered to be a folded, specialized leaf.
Notes:

The ovaries are hypothesized to be comprised of varying numbers of carpels which can generally be determined by equating the number of carpels to the number of locules, stigmatic lobes, or stigmatic lines. In neotropical Lecythidaceae, the number of locules varies and is useful for helping to distinguish genera, e.g. species of species of Couroupita have six carpels, species of Grias almost always have four carpels, species of Couratari three carpels, and species of Eschweilera have two carpels. There is, however, some variation in carpel number such that a species with four carpels can have some ovaries with three and others with five carpels.
Related Terms:

Ovary
Locule