A general feeling of unease or vague anxiety, usually caused by mildly to moderately awkward social situations and sometimes involving inappropriate or unwanted displays of affection among persons whom are young or unfamiliar.
"Did you see that guy making kissy faces at me over there?"
"Yeah, he's creepy... he gives me the heeby-jeebies!"
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"Can you believe those two? They're only in sixth grade!"
"Word. They're a little young for that... it kinda gives me the heeby-jeebies."