Teacher of Economics   

Kiss is the object for which the demand is always higher than the supply. 

Teacher of Accountancy     

Kiss is a credit because it is profitable when returned. 

Teacher of Algebra     

Kiss is infinity as two are divided by nothing.

Teacher of Geometry     

Kiss is the shortest distance between two pairs of lips.

Teacher of Physics     

Kiss is the contraction of mouth due to the expansion of the heart. 

Teacher of Chemistry     

Kiss is the reaction of the interaction between two hearts. 

Teacher of Zoology     

Kiss is the interchange of salivary bacteria.

Teacher of Physiology     

Kiss is the juxtaposition of two orbicularisoris muscles in the state of contraction. 

Teacher of Dentistry     

Kiss is infectious and antiseptic.

Teacher of Philosophy     

Kiss is the persecution for the child, ecstasy for the youth and homage for the old. 

Teacher of English     

Kiss is a noun that is used as a conjunction, it is more common than proper, it is spoken in the plural and it is applicable to all. 

Teacher of Architecture     

Kiss is a process which builds a solid bond between the two dynamic objects 

Teacher of Computer Science     

What is a kiss? It seems to be an undefined variable