You may personally consider it to be a pick but by definition it isn't one. What you're describing would be known as a 'Bounced'. When you attack another player that isn't aware of your presence, you've 'bounced' him. It's really not a subjective thing, it's an already established term to explain the situation you described.
When the term isn't clearly defined, then there will always be different perspectives and opinions on the meaning. However, with terms like "Cherry Pick", "Vulch", "Bounce", the terms are already clearly defined and their definitions have been widely accepted for decades, there is no subjective meanings to these terms. A "Cherry Pick (or just plain "Pick") is the act of engaging an enemy that is already enaged with another bandit. A "Vulch" is the act of engaging an enemy as they are in the process of either taking off or landing. A "Bounce" is the act of engaging an enemy that is unaware of your presence.
ack-ack
a couple additions if i may?
vulching,,,,is during the landing or take off process. it should be noted, that part of the landing process is final approach.
i've heard some say things like "you weren't even at the runway" after vulching someone. well......they were on final, low n slow, probably gear and flaps out. it's still a vulch.
same on take off.........if you're not allowing a con to gain fighting speed, because he's still just wheels up,,,,,,,you just vulched the dude.
and finally....i think it is possible to bounce someone that knows you're there. they may not have seen ya till only a few seconds before guns, but they've still been bounced, if they're lower than you.