propositus

[pruh-poz-i-tuh s] /prəˈpɒz ɪ təs/
noun, plural propositi
[pruh-poz-i-tahy] /prəˈpɒz ɪˌtaɪ/ (Show IPA)
1.
Law. the person from whom a line of descent is derived on a genealogical table.
2.
Genetics. proband.
Origin
1925-30; < Neo-Latin, special use of past participle of Latin prōpōnere to set forth, propound
British Dictionary definitions for propositus

propositus

/prəˈpɒzɪtəs/
noun (pl) -ti (-ˌtaɪ), (fem) -tae (-tiː)
1.
(law) the person from whom a line of descent is traced
2.
(med) Also called (esp US) proband. the first patient to be investigated in a family study, to whom all relationships are referred
Word Origin
from New Latin, from Latin prōpōnere to set forth; see propound
propositus in Medicine

propositus pro·pos·i·tus (prō-pŏz'ĭ-təs)
n. pl. pro·pos·i·ti (-tī')

  1. See proband.

  2. A premise; an argument.