in brief inb·rief uncommon adverb 1. in a concise manner; in a few words “the history is summed up concisely in this book” “she replied briefly” “briefly, we have a problem” “to put it shortly” Synonymsconciselybrieflyshortlyin briefin short Related words Pertaining to briefconcise WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.