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.
By Robert Emmons | September 10, 2014. The author of Thanks! introduces the science of gratitude at the Greater Good Gratitude Summit in June 2014. Gratitude is for Lovers By Amie M. Gordon | February 5, 2013. New research says thankfulness, not romance, might be key to a happy Valentine's Day.y Robert Emmons | September 10, 2014. The author of Thanks! introduces the science of gratitude at the Greater Good Gratitude Summit in June 2014. Gratitude is for Lovers By Amie M. Gordon | February 5, 2013. New research says thankfulness, not romance, might be key to a happy Valentine's Day.