We saw a giraffe at the zoo. (Here, a giraffe is some giraffe in general).
The giraffe is the tallest animal. (Here, the giraffe is a type of animal).
But what should I say in the following case:
My girlfriend and I are walking around the zoo. Then going past a cage with a giraffe, I say to her "Misty, ? giraffe gave me a smile!"
What word ought I to put before "giraffe"? If I use "the", it will mean "a type of animal", isn't it?.. There remains only "this" or "that"...