The kanji 係 primarily conveys the idea of "to be in charge of," "to relate to," "to be connected to," or "a person in charge/a person responsible." It implies a relationship, responsibility, or connection.

・On-yomi (音読み): ケイ (kei) ・Kun-yomi (訓読み): かかる (kakaru)

⚫︎ 係員 (keiin) Translation: Staff member; person in charge. ⚫︎ 関係 (kankei) Translation: Relation; relationship; connection. ⚫︎ あの件に関係係している (Ano ken ni kankei係shiteiru) Translation: To be related to that matter.

The kanji 係 is a 形声文字 (keisei moji), a phono-semantic compound character. The left side, 亻 (ninben), is the radical meaning "person." The right side, 系 (kei), acts as the phonetic component and gives a clue to the sound of the character. 系 originally means "to tie" or "a thread." The combination suggests a person being tied to a duty or relationship, thus "to be in charge of" or "to be related to."