Black's Law Dictionary (2nd edition)dictionaries

Obsta Principiis

Lat. withstand beginnings; resist the first approaches or encroachments. “It is the duty of courts to be'watchful for the constitutional rights of the citizen, and against any stealthy en-croachments thereon. Thelr motto should be *obsta principiis: ” Bradley, J., Boyd v

Source: Black's Law Dictionary 2nd Ed (1910)