下位互換性[kaigokansei] downward compatibility
互い[tagai] mutual
互いに[tagaini] mutually
互い違い[tagaichigai] alternate
互い違いに[tagaichigaini] alternate

互に[katamini] mutually
互角[gokaku] equality
互換[gokan] transposition
互換性[gokansei] compatibility
互恵[gokei] reciprocity

恩恵[onkei] grace
恵み[megumi] blessing
恵む[megumu] to bless
恵沢[keitaku] blessing
恵比須[webisu] Ebisu (god of fishing and commerce)

互恵[gokei] reciprocity
最恵国待遇[saikeikokutaiguu] most favored nation
三人寄れば文殊の知恵[sanninyorebamonjunochie] two heads are better than one
慈恵[jikei] mercy and love
仁恵[jinkei] graciousness