This is the 237th most frequent Korean word.
조사
"조사" refers to particles used in Korean grammar to indicate the relationship between words in a sentence.
The word '조사' in this context is used as a noun meaning 'investigation' and is part of the verb '조사하다' (to investigate).
경찰이 범인을 찾기 위해 사건을 조사하고 있다.
The police are investigating the case to find the suspect.
Here, '조사' refers to grammatical particles in the Korean language.
한국어에는 다양한 문법 조사가 있습니다.
In the Korean language, there are various grammatical particles.
In this sentence, '조사' refers to investigation or survey as a systematic method of collecting data.