Jaculator:- A hook-like process on the stalk of a seed  that helps in dispersal.
Junciform:- Reed-like; growing like a rush

Keel:- A petal which has a sharp keel-like edge - as the keel of a boat. The lower petal in a pea-flower

Labiate:- A member of the mint family, Labiatae.
Lacerate:- Irregularly lobed at the margin  -  as if torn
Lacinia:- A jagged or irregular part of a leaf or petal.
Laciniate:- Cut into slender lobes or drawn-out teeth.
Lamelliform:- with thin plates stacked on top or next to each other
Blade. the expanded part of the leaf or petal.
Limb:- The border or upper spreading part of a petal or sepal.
Lanate:- (lanuginose):- With long dense curly interwoven matted woolly hairs
Lanate-tomentose:- With long dense curly interwoven matted woolly hairs or short, dense, matted hairs.
Lanate-villous:- With long shaggy dense curly interwoven matted woolly hairs
Lance-shaped: more or less elliptical but broadest below the middle.
Lanceolate-filiform:- Lance-shaped-thread-like
Lanuginose:- Covered with down, covered with fine soft hairs; downy.
Latex:- Milky juice or sap produced by stems, leaves and other or­gans. It may be white or variously coloured.
Lax:- Loose.
Legume:- A member of the pea family, Leguminosae.
Lemma:- The lower of two bracts enclosing the flower: in grasses.
Lenticular:- Discoid witha convex lens-shape
Lepidote: Covered with scurfy scales or scaly spots.
Ligulate:- 1)
strap-shaped, narrow and with parallel sides; 2) with a ligule;
3) (in Compositae inflorescences) denoting the presence of florets with a ligule
Ligule:- A small flap of tissue, often located at the base of a leaf of petal.
Linear:- Narrow and parallel-sided. Narrow and much longer than wide, with parallel margins.
Linear - Subspatulate:- Narrow, parallel-sided to almost spatulate.
Lingulate:- Tongue-shaped
Lip:- A petal or petals (occasionally the sepals) which form a dis­tinct organ sharply divided from the other petals or sepals and which acts as a landing stage for visiting insects. 2-lipped flowers have both an upper and a lower lip, the upper forming a hood.
Lobe:- Roundish and flattish part of something, typically each of two or more such parts divided by a fissure, and often projecting or hanging.
Lobed:- Divided but not separated entirely. Leaves, for instance, may be shallowly or deeply lobed.
Locule:- (plural loculi), 1). the cavity of the carpel in which the ovule or ovules are borne; 2). the compartment of an anther in which the pollen is borne; 3). the cavity in a sporangium
Loculicidal:- When a ripe capsule splits into the cells, i.e. splits not at the lines of junction between the locules (i.e. septa) but along the midrib or dorsal suture.capsule splitting into the cells, along the midrib or dorsal suture
Loment, Lomentum:- A flat fruit, constricted between each seed and falling apart at the constrictions into separate parts
Lorate:- Strap-shaped, usually more broadly than in ligulate.
Lunate:- Half moon-shaped, crescent-shaped.
Lyrate:- Lyre-shaped, pinnately lobed proximally but with a large rounded terminal lobe.