靠 (kào) means to lean on, rely on, or depend on. Physically it describes something resting against a surface (靠墙, lean against a wall). Figuratively it means to rely on or depend on (靠朋友, rely on friends; 靠运气, rely on luck). 靠不住 (cannot be relied upon) and 靠得住 (reliable) are common expressions. 靠近 (kào jìn) means near or to approach. In casual speech 靠 can also function as a mild exclamation of frustration.