1.
fundamental; basic; foundational
Relating to the foundation or basics of something. Used to describe knowledge, skills, research, or conditions that form the essential groundwork.
Common collocations: 基礎的な知識 (fundamental knowledge), 基礎的な研究 (basic/fundamental research), 基礎的な体力 (basic physical fitness), 基礎的な能力 (basic ability). Compare with 基本的 (basic — more commonly used in everyday speech) and 根本的 (fundamental — implies getting to the root cause). 基礎的 is often used in academic and formal contexts.