youngest / most junior / tiny / one (unambiguous spoken form when spelling out numbers, esp. on telephone or in military) / one or ace on dice or dominoes / variant of 吆[yao1], to shout
particle indicating that a previously asked question is to be applied to the preceding word ("What about ...?", "And ...?") / particle for inquiring about location ("Where is ...?") / particle signaling a pause, to emphasize the preceding words and allow the listener time to take them on board ("ok?", "are you with me?") / (at the end of a declarative sentence) particle indicating continuation of a state or action / particle indicating strong affirmation