The Britannica Dictionary
mobile search
Home
Ask the Editor
Word of the Day
Quizzes
Core Vocabulary
Browse the Dictionary
×
Britannica Homepage
Ask the Editor
Word of the Day
Quizzes
Core Vocabulary
Browse the Dictionary
The Britannica Dictionary
Ob
3 ENTRIES FOUND:
Ob
(proper noun)
ob–gyn
(noun)
OB–GYN
(abbreviation)
Ob
/
ˈ
ɑːb/
proper noun
Ob
/
ˈ
ɑːb/
proper noun
Britannica Dictionary definition of OB
the Ob River
also
the Ob
:
river in Russia
ASK THE EDITOR
Why do we say "did you know" rather than "do you know"?
See the answer »
QUIZZES
Vocabulary Quiz
Test your word power
Take the Quiz »
Name That Thing
Take our visual quiz
Test Your Knowledge »
WORD OF THE DAY
protocol
:
a system of rules that explain the correct conduct and procedures to follow in formal situations
Learn More »