Top Definition
Integral to both the structure and function of an object. Originally used to discribe nitrogenous bases in the DNA double helix it has come to describe a wide variety of biologically important molecules.
In biology: Nitrogenous bases are critically important structional components of the DNA double helix.

In manufacturing: The rungs of a ladder strunctionally support its purpose.
by RossBrock March 30, 2009

The Urban Dictionary Mug

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The Urban Dictionary Mug

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The Urban Dictionary Mug

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The Urban Dictionary Mug

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