U
- umbel
- (adjective umbellate) a racemose inflorescence in which all the individual flower stalks arise in a cluster at the top of the peduncle and are of about equal length; in a simple umbel, each stalk is unbranched and bears only one flower; a cymose umbel is an apparent umbel but its flowers open centrifugally.
- umbonate
- with a conical or blunt projection arising from a flatter surface, as on the top of a mushroom, or in the scale of a pine cone.
- uncinate
- with a hook at the apex.
- undershrub
- a low shrub, often with flowering branches that die off in winter; cf. subshrub.
- undulate
- wavy and not flat; compare sinuate.
- unilocular
- having one loculus or chamber, e.g., the ovary in the families Proteaceae and Fabaceae.
- uniserial
- Arranged in a single row or series. Unbranched. Uniseriate.
- uniseriate
- Arranged in a single row or series. Unbranched. Uniserial.
- unisexual
- of one sex; bearing only male or only female reproductive organs.
- unitegmic
- (of an ovule), covered by a single integument.
- urceolate
- urn-shaped.
- utricle
- a small bladder; a membranous bladder-like sac enclosing an ovary or fruit; in sedges a fruit in which the pericarp is larger than, and loosely encloses, the seed.
Read more about this topic: Glossary Of Botanical Terms