Kootu is a lesser known part of TamBram cuisine. While the Sambhars and Rasams have been immortalised by the flourishing Udipi restaurants, kootu is something you will only find in a household and rarely ever in a restaurant.
From Wikipedia: Kootu is a Tamil dish, common in both Tamil Nadu and South India. Kootus are essentially vegetable and lentil dishes which are semi-solid, i.e., less aqueous than sambhar, but more so than dry curries. Rice and kootu is a common and simple Tamil meal. In Tamil cuisine kootus are considered substitutes for both curries and sambhar.
All kootus by default have some vegetables and lentils, but many variations of kootu exist:
Puli Kootu: Puli is the Tamil word for tamarind and puli kootu refers to a kootu made with tamarind.
Poricha Kootu: A kootu made with moong beans and cocunut.
Araichivita Kootu: A kootu which has a ground (freshly powdered) masala in it, where the word araichivita in tamil literally translates to ‘the one which has been ground and poured’.
Many other regional variations exist.
By the above definitions, this Snake Gourd Kootu would fall under category 2 and 3 as it has moong dal or tur dal, coconut and the masala is freshly ground.
While Tamilians have a fondness for all gourds, even some of those that other cuisines wont touch, snake gourd is one of the popular ones. In addition to this preparation, it is also made in dry curry form, where udad dal, dried red chilli pieces and mustard seeds are tempered in oil, the slices of gourd are cooked till tender by sprinkling some water, seasoned with salt and garnished with fresh coconut.