Phaladeepika
क्षेत्रत्रिभागनवभागदशांशहोरात्रिंशंशसप्तलवषष्टिलवाः कलांशाः । ते द्वादशांशसहिता दशवर्गसंज्ञा वर्गोत्तमो निजनिजे भवने नवांशः ॥ १॥
(Kshetra or an arc of 30), Drekkana, Decanate or an arc of 10°), (Navamsa or an (Dasamsa or an arc of 3" or 1 portion (Hora or of a sign, i.e., an arc of 15°), (Trimsamsa or portion of a sign, i.e., an arc of 1°), (Saptamsa or th portion of a sign, i.e., an arc of 4°), l(Shashtyamsa or th portion of a sign, i.e., an arc of °) and (Kalamsa or i portion of a sign, i.e., an arc of 17°)-these along with the (Dwadasamsa or portion of a sign, i.e., an arc of 21°) are termed Dasa Vargas or ten-fold divisions of the Zodiac. (Vargottama) is the name given to that particular Navamsa in a Rasi which bears the same name as that of the Rasi itself.
english translation
kSetratribhAganavabhAgadazAMzahorAtriMzaMzasaptalavaSaSTilavAH kalAMzAH । te dvAdazAMzasahitA dazavargasaMjJA vargottamo nijanije bhavane navAMzaH ॥ 1॥
hk transliteration by Sanscript