左膀右臂

trusted assistant; key aide

surname Zuo

left / the Left (politics) / east / unorthodox / queer / wrong / differing / opposite / variant of 佐[zuo3]

upper arm / wing

used in 吊膀子[diao4 bang4 zi5]

puffed (swollen)

bladder

old variant of 膀[bang3]

right (-hand) / the Right (politics) / west (old)

(bound form) right; right-hand side / (bound form) (politics) right of center / (bound form) (old) west / (literary) the right side as the side of precedence

arm