込 (readings: -こ, こ; Japanese kanji) means “Crowded / Mixture / In Bulk / Included”. It is a Jōyō kanji taught in Japanese secondary school (junior & senior high) — the 高手 · Master tier beyond the grade 1–6 Kyōiku set, and appears in words such as 申し込む (to apply).
What does 込 mean?