ソウ, ショウ, あい, あ, い, おう, さ, さが, すけ
inter-, mutual, together, each other, minister of state, councillor, aspect, phase, physiognomy
JLPT3 G3 S9 F45
目 here an abbreviated form# of 省 (observe) + 木 tree/wood → eyes focused on an object (establishing a *mutual* relation between observer and observed) → *together*; *watch*; *assist*; *assistant*; *shape*; *appearance* → (grammatical) *voice*; *emphatic verbal prefix*. Also, *minister* (← one who assists a ruler).
[Full Kanji Etymology List]