Hog, n. A bird remarkable for the catholicity of its appetite and serving to illustrate that of ours. Among the Mohammedans and Jews, the hog is not in favor as an article of diet, but is respected for the delicacy of its habits, the beauty of its plumage and the melody of its voice. It is chiefly as a songster that the fowl is esteemed; the cage of him in full chorus has been known to draw tears from two persons at once. The scientific name of this dicky-bird is Porcus Rockefelleri. Mr. Rockefeller did not discover the hog, but it is considered his by right of resemblance.
2006 Update: A discrete euphemism for a valued coworker.