Someone's Effect? The word "effect" does not appear on the card, and I think the best answer is No.
Astronomical? No.
Nash Equilibrium? The best response is No.
Visible? *audience goes "oooooh"*. I think I have to say Yes and No. Either 'Yes" or 'No' could be justified as an answer, and by the same token either would be misleading.

Schelling point? No. (the audience communicates by a subtle combination of laughter, applause and silence that, had this been the correct answer, they would have given some recognition to 'Nash equilibrium')
Cerenkov radiation? No.

A hologram? No.
Connected with economics? Isn't everything? But, otherwise, No.
Connected with particle physics? Isn't everything? But, otherwise, No.

Temperature dependent? Yes.
To do with meteorology? Yes. *applause*
Before 20th century? Yes.

I think that is close enough for me to award a mercury-filled baton to irach, even though it was not posed as a guess. The answer on the card was "A Torricelli (or Torricellian) Vacuum".

The subject was prompted by the fact that I almost guessed "vacuum" for Rosie's recent AVMA about a day before it was correctly guessed (no, really, I did), but then rejected it on the grounds that Rosie had claimed no connection to the weather. :-) (That's not intended as a criticism, btw; on reflection I thought that Rosie's answer was probably right.)

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Let me then step in to fill the void... The next one is simply ANIMAL

[Raak] Not human.