1
general::
Phrase(s): in brief
briefly; concisely. • The whole story, in brief, is that Bob failed algebra because he did not study. • Please tell me in brief why you want this job.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Also, in short;in a word. Concisely, in few words, to sum up. All three phrases usually precede or follow a summary statement, as in In brief, we didn't get much out of his speech, or There was no agenda; in short, they could discuss whatever they wanted to, or The sun was shining, the sky was clear? in a word, it was a beautiful day. The first expression dates from the early 1400s; in short dates from the 1300s but the present usage dates from the 1700s; the hyperbolic in a word (since there is nearly always more than one word) dates from the late 1500s.
American Heritage Idioms