Portik is literally portico (a lesser used English term derived from Latin), the definition is found below.

It generally refers to the very lavish columned entryways of the Renaissance, which you find repeated in the American South, etc. For pictures, see:http://www.architrave.net/portico/ (direct link included below)

However, dependant on your readership as well as the exact entry to which this refers, I would possibly use "ornate porch or entryway". Saying simply "porch" would not really indicate the grandeur of the entrance, but "portico" may be overkill.

por·ti·co ( P ) Pronunciation Key (pôrt-k, pr-)
n. pl. por·ti·coes or por·ti·cos
A porch or walkway with a roof supported by columns, often leading to the entrance of a building.


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[Italian, from Latin porticus, from porta, gate. See per-2 in Indo-European Roots.]
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porti·coed adj.

Source: The American Heritage® Dictionary of the English Language, Fourth Edition
Copyright © 2000 by Houghton Mifflin Company.



Hope this helps!

Cheers,
Paula