noun
initial stage; early period; founding era
Refers to the very beginning or formative period of an organization, project, field, or era. Often used in historical or business contexts.
会社の創成期には、社員はわずか5人だった。
In the company's early days, there were only five employees.
この技術はインターネットの創成期に開発された。
This technology was developed in the early days of the internet.
Compound of 創成 (そうせい, 'creation, founding') + 期 (き, 'period'). The kanji 創 means 'to create', 成 means 'to become' or 'to accomplish', and 期 means 'period' or 'time'.