The kanji 及 primarily conveys the idea of "reaching," "extending," or "and." It implies something that extends to, encompasses, or affects something else. It can also mean "to reach," "to arrive at," or "to equal." Essentially, it is about expansion, connection, and inclusion.

・On-yomi (音読み): きゅう (kyū) ・Kun-yomi (訓読み): および (oyobi) - to reach, およぶ (oyobu) - to extend to; to affect.

⚫︎ 及第 (きゅうだい) Translation: Passing (an exam). ⚫︎ 普及 (ふきゅう) Translation: Diffusion; spread; popularization. ⚫︎ 学力に及ばない (がくりょくにおよばない) Translation: Not reaching (one's) academic ability.

The kanji 及 is a pictograph. It depicts a person (represented by a vertical line) and something extending towards them (represented by a horizontal line that slightly leans downwards). The whole indicates an arm reaching out, or something extending to reach someone or something else. Over time, the form has simplified. It is a visual representation of the concept of extending or reaching.