What is a Kiss?

Prof. of Computer Science: A kiss is a few bits of love compiled into a byte.
Prof. of Algebra: A kiss is two divided by nothing.
Prof. of Geometry: A kiss is the shortest distance between two straight lines.
Prof. of Physics: A kiss is the contraction of mouth due to the expansion of the heart.
Prof. of Zoology: A kiss is the interchange of unisexual salivary bacteria.
Prof. of Physiology: A kiss is the juxtaposition of two orbicular ors muscles in the state of contraction.
Prof. of Dentistry: A kiss is infectious and antiseptic.
Prof. of Accountancy: A kiss is a credit because it is profitable when returned.
Prof. of Economics: A kiss is that thing for which the demand is higher than the supply.
Prof. of Philosophy: A kiss is the persecution for the child, ecstasy for the youth and homage for the old.
Prof. of Engineering: Uh, What? I'm not familiar with that term."
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