Top Definition
When someone you have just met friends or messages you on facebook via smartphone during the time it took you to leave the bar and get home.
"Holy sh*t, she instastalked me. I can't decide if that's cool or not."

Or

"Don't friend her yet, your too close to instastalk territory."
by Drewsmits February 09, 2010

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verb:
To stalk someone on Instagram.

This is a development from the traditional Facebook stalk, as there are many more users that will allow their Instagram account to be public, and therefore open to Instastalkers (noun).
I know she goes to the gym, because I instastalked her.

I've made my Instagram account public, so everyone can instastalk me.
by Buggiful January 30, 2014

The Urban Dictionary Mug

Lotsa space for your liquids.

Buy the mug

The Urban Dictionary Mug

Lotsa space for your liquids.

Buy the mug

The Urban Dictionary Mug

Your favorite word on a white mug.

Create a mug

The Urban Dictionary Mug

One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.

Buy the mug

The Urban Dictionary T-Shirt

Soft and offensive. Just like you.

Buy the t-shirt

The Urban Dictionary T-Shirt

Smooth, soft, slim fit American Apparel shirt. Custom printed. 100% fine jersey cotton, except for heather grey (90% cotton).

Buy the t-shirt