The Greeva Bhedas are the classifications of the movements of the neck.

“Sundari cha tiraschina tathaiva parivartita
Prakampita cha bhavajnaih jneya greeva chaturvidha”

This shloka explains that the scholars on bhavas know that there are fourfold classifications of the neck movements, i.e., Sundari, Tiraschina, parivartitaa and prakampitaa.

SUNDARI GREEVA:
“Tiryak Prachalitaa Greevaa sundareeti nigadyate
Snehaarambbhe tathaa yatne Samyagarthe api cha smrtou
Sarasatwe anumode cha saa greevaa sundareeti mataa”

This means that when the neck is moved obliquely or horizontally, it is sundari greeva.
It is used to show beginning of friendship, effort, saying “well done”, recollection, badinage and acceptance.

TIRASCHINA GREEVA:
“Paarswadwayodhwa bhaage tu chalitaa sarpayaanavat
Saa greevaa tu tiraschiinetyuchyate naatyakovidaih
Khadgabhrame sarpagatyaam tirascheena prayujyate”

Experts believe that the upward movement of the neck on both sides , like the gliding of the snake, is tirascheena greeva. It is used to denote the brandishing of a sword and serpentine progression.

PARIVARTITA GREEVA:
“Savyaapasavya chalitaa greevaa yatraardha chandravat
Saahi naatyakalaabhijnaiha vijneyaa parivartitaa
Shringaara natane kaantaa kapoladwaya chumbane
Naatya tantra kalaabhijnaih prayojyaa parivartitaa”

When the neck moves to the right and the left like a half moon , t is known as parivartitaa by the experts. It is used to show erotic dances to show kissing both the cheeks of the charming beloved.

PRAKAMPITA GREEVA:
“Purahpashchaat Prachalanaat Kapotikantha kampavat
Prakampeti saa greeva Naatyashaastre prashasyate
Yushma dasmaditi prokte desinaatye Visheshataha
Dolaayaam manite chaiva prayoktavyaa prakampita”

When the neck moves forward and backward like that of a she pigeon, it is recognized as the prakampita greeva. It is used to say ‘you and I’ in desi naatye; swinging and sweet sounds produced as if by a she pigeon.