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Suppose you have a conductor A, surrounded by other conductors - B1, B2, ... BN.
Apply a voltage V to conductor A, while all other conductors are grounded.
Measure/calculate charge change on each of conductors - Q_A, Q_B1, Q_B2, ... Q_BN.
Total capacitance of conductor A is C_A = Q_A / V.
Capacitance between conductors A and B1 is C_A_B1 = Q_B1 / V, between A and B2 is C_A_B2 = Q_B2 / V, and so on.
Capacitance between A and B1 is also called coupling capacitance between A and B1.
The total capacitance of A is equal to the sum of coupling capacitances: C_A = C_A_B1 + C_A_B2 + ... + C_A_BN.
Capacitance between A and B1 is equal to capacitance between B1 and A - so, capacitance is symmetric, in electrostatics.
You see, coupling or total capacitance, defined as above, has nothing to do with capacitance being parasitic or non-parasitic (i.e. intended).
I think the term "coupling" is meant to describe a partial capacitance between a conductor A and other conductor - as opposed to the total capacitance of A.
Now, capacitance can be intended, created on purpose - such as MOM capacitor, MIM capacitor, MOS capacitor, decoupling capacitor, energy storing capacitor, etc.
Or it can be unintended, unwanted, but present because of physical size and proximity of conductors - in this case, it is called parasitic.
The term "parasitic" can be applied to both total capacitance, and partial (coupling) capacitance.
Coupling Capacitor: B/w to stages you put a capacitor that allows only AC to next stage and blocks any DC shift from going to next stage.
Decoupling capacitor: usually b/w where you only want DC level at a certain point, connected to ground and allows any AC noise to ground not effecting DC level.
Parasitic Capacitance: That develops unwanted either because two conductors are placed close to each other or other