On tiptoe is an idiomatic expression that refers to walking or standing on the balls of your feet. This posture is usually adopted when one needs to move quietly or stealthily. There are many synonyms for on tiptoe, including walking or standing on tiptoe, stepping lightly, lightly treading, stepping softly, taking soft steps, moving quietly, shuffling noiselessly, walking cat-like, and creeping stealthily. All these expressions refer to moving or standing quietly, cautiously, or in a stealthy manner. Each of them conveys a slightly different nuance in meaning but essentially describes the same thing - being on tiptoe.