隠密[onmitsu] privacy
過密[kamitsu] overcrowding
確率密度関数[kakuritsumitsudokansuu] probability density function
機密[kimitsu] secrecy
機密性[kimitsusei] confidentiality

機密保護[kimitsuhogo] security (e.g. data, password, etc.)
気密[kimitsu] airtight
気密室[kimitsushitsu] airtight chamber
緊密[kinmitsu] rigour
軍事秘密[gunjihimitsu] military secret

一封[ippuu] sealed letter
開封[kaifuu] unsealed letter
完封[kanpuu] complete blockade (seal)
旧封[kyuuhou] former fief
厳封[genpuu] sealing hermetically

言論を封殺する[genronwofuusatsusuru] to suppress the freedom of speech
御封[gofu] talisman
再封鎖[saifuusa] reblocking
三封[sanpuu] forced out on third
全封地[zenhouchi] the whole fief