What does «ob» mean in Spanish?

Inseparable preposition of Latin origin meaning: because of, by virtue of, by force of. It is used in voices of Latin origin.
(ob / obs) Latin prefix giving the idea of "in front with opposite orientation to the given orientation", i.e., confrontation, opposition, impediment or obstacle.
(Ob.) Abbreviation suggested by the RAE for "bishop".
(ob. cit.) Abbreviation suggested by the RAE for "obra citada".
(O.B.) Abbreviation for "bimember sentence".
(Ob) City (pop. 29,437, year 2018, in Novosibirsk oblast) and river (in western Siberia) of Russia. In English it is also transliterated as "Obi".
(estrellas OB) In astronomy, they are hot, massive stars of spectral type O or early type B that form in loosely organized groups called OB associations. They are short-lived, and therefore do not move far from where they formed within their lifetime. During their lifetime, they will emit a lot of ultraviolet radiation. This radiation rapidly ionizes the surrounding interstellar gas of the giant molecular cloud, forming an H II region or Strömgren sphere.