secrecy, density (pop), minuteness, carefulness
密 centers on things being packed tightly together, whether physically dense, meticulously detailed, or kept close and hidden. Secrecy and carefulness are natural extensions of keeping something tightly contained.
密 combines 宓 (a phonetic component suggesting quietness or stillness) with 山 (mountain), together conveying the idea of a dense, secluded mountain area. The modern meanings of secrecy and minuteness derive from this sense of tight, quiet enclosure.
Picture a mountain (山) with a quiet, still presence (宓) covering it like a thick forest. Everything is packed tightly together, hidden and careful.
For ミツ, imagine a dense forest so thick that you need a machete (ミツ sounds like 'mits' as in 'mitts') to cut through the secrecy and minuteness of the undergrowth.
secret; secrecy; confidentiality; privacy
secrecy; highly classified information
secret; private; surreptitious
close adhesion; sticking firmly (to); being glued (to)
density
precise; exact; detailed; accurate; minute; close
close (relationship, connection, etc.); intimate; near
intimacy; friendship
locked room
smuggling; contraband trade
crowding together; clustering together; close formation; swarm
fine (grain, workmanship, etc.); close (weave); delicate; intricate; elaborate
minute; detailed; careful; scrupulous; thorough
illicit sale; smuggling; bootlegging; trafficking
overcrowding; congestion; overpopulation
close thicket; dense forest; jungle
secret agreement
rigour; rigor; closeness; compactness; tightly knit
poaching
stowing away; smuggling oneself; clandestine travel abroad
smuggling oneself into a country; illegal immigration
strict; close; precise; scrupulous