The weather is suitable outdoors for the activity you want to participate it. Sunny for a walk or a swim. Snowing for sking. Windy for sailing. If it's the weather you want outside then for you it's outdoorable.
"Oh look, it's outdoorable. Bring your coffee and let's sit in the sun."
"There's a good wind coming up, perfect for windsurfing. Yes finally it's outdoorable."
Any indoor item that can be used outdoors without getting ruined by the elements.
Me- I'm going to go get my favorite chair to sit on outside with you guys.
Them - what? you're favorite indoor chair? Won't it get ruined and dirty?
Me- No! It's OK, it's totally outdoorable.
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"