Real Dictionary

D.O. in American English
abbreviation: direct object

ditto in British English
adverb: in the same way
noun: the aforementioned; the above; the same. Used in accounts, lists, etc, to avoid repetition and symbolized by two small marks (〃) known as ditto marks, placed under the thing repeated
sentence substitute: used to avoid repeating or to confirm agreement with an immediately preceding sentence
verb: to copy; repeat

do auxiliary verb uses
auxiliary verb: Do is used to form the negative of main verbs, by putting 'not' after 'do' and before the main verb in its infinitive form, that is the form without 'to'.

DO in American English
ditto
Doctor of Osteopathy

do in American English 1
(used in interrogative, negative, and inverted constructions)
to execute; effect; perform (an act, action, etc.)
intransitive verb: to act or conduct oneself; be in action; behave
transitive verb: to perform (an act, duty, role, etc.)

do in American English 2
a syllable representing the first or last tone of the diatonic scale
noun: the syllable used for the first tone or keynote of a diatonic scale

do in American English 3
hairdo

do in British English
to act like; imitate
abbreviation for: Doctor of Optometry

do in British English 1
verb: to perform or complete (a deed or action)

do in British English 2
noun

do in British English 3
the internet domain name for: Dominican Republic

do noun uses
countable noun: A do is a party, dinner party, or other social event.

do other verb uses
verb: Do can be used to stand for any verb group, or to refer back to another verb group, including one that was in a previous sentence.
verb: If you do a particular thing with something, you use it in that particular way.
verb: If you do something about a problem, you take action to try to solve it.
verb: When you do something, you take some action or perform an activity or task. Do is often used instead of a more specific verb, to talk about a common action involving a particular thing. For example you can say 'do your teeth' instead of ' brush your teeth
verb: You can use do in a clause at the beginning of a sentence after words like 'what' and 'all', to give special emphasis to the information that comes at the end of the sentence.

do.
do. is an old-fashioned written abbreviation for ditto.

do. in American English
abbreviation: ditto

do. in British English
abbreviation for: ditto