“Reticent” most often means “reluctant to speak.” It can also mean “reserved,” “restrained,” though conservatives prefer to use it to apply only to speech. If you’re feeling nervous about doing something, you’re hesitant: “I’m hesitant about trying to ride a unicycle in public.” “Hesitant” is by far the more common word; so if you hesitate to choose between the two, go with “hesitant.”
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