Many sulci are the product of a surface fold or junction, such as in the gums, where they fold around the neck of the tooth. The term sulcus is used in invertebrate zoology to describe folds, grooves, and boundaries, especially at the edges of sclerites or between segments. In botany and palynology, the surface morphology of seeds and pollen grains is termed sulcate if one or more sulci form major features.
Freebase(0.00 / 0 votes)Rate this definition: Gratitude. Gratitude, thankfulness, gratefulness, or appreciation is a feeling or attitude in acknowledgment of a benefit that one has received or will receive.
Definition of reward. 1 : something that is given in return for good or evil done or received or that is offered or given for some service or attainment the police offered a reward for his capture. 2 : a stimulus (such as food) that is administered to an organism and serves to reinforce a desired response.