My friend " Ko Cho" (England) asked me the meaning of Carnations.
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Carnations mean a lot as Roses do.
Solid Colour Carnation :
Yes
White Carnation :
Sweet and Lovely, Innocence, Pure Love, Woman's Good Luck Gift 
Striped Carnation :
No Refusal, Sorry I Can't Be With You, Wish I Could Be With You
Pink Carnation: I'll Never Forget You
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Purple Carnation :
Capriciousness, Whimsical
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Yellow Carnation :
You Have Disappointed Me, Rejection
Red Carnation :
My Heart Aches For You, Admiration