Q: We’re planning to hold a reception “on” the West Porch of our museum. Or do we say “in” that particular room? Does it matter whether the room is enclosed?
A: The noun “porch” can refer to either an exterior, covered structure at the entrance of a building or an interior vestibule or hallway, according to the Oxford English Dictionary.
The American Heritage Dictionary of the English Language (4th ed.) says it can also refer to an open or enclosed room attached to the outside of a building.
We haven’t found any authoritative answer to your question about the appropriate prepositions.
But we ourselves happen to prefer “on” for exterior, open structures and “in” for enclosed, interior areas.
For example, in referring to an exterior, unenclosed porch we would say, “In summer we put the potted palm outside on the porch.”
But if we called our entry hall or vestibule a “porch,” we would say, “Come inside and leave your wet things in the porch.”
We may not be in the majority, however. A cursory Google search of “in the porch” turned up eight times as many hits as a search for “on the porch.”
The word “porch” entered English around 1300, according to the OED. A brief examination of the OED citations shows an early preference for “in” rather than “on.”
For example, this comes from William Langland’s poem Piers Plowman (circa 1400): “I hym seigh as I satte in my porche.” (“I saw him as I sat in my porch.”)
The word came into English by way of Anglo-Norman and was originally spelled like the French porche. The word’s ultimate ancestor is the Latin porticus (a colonnade, arcade, or porch).
In fact, English borrowed “porticus” itself directly from Latin in the early 17th century, and it’s still sometimes used as an architectural term today.
The OED describes a “porticus” as “a formal entrance to a classical temple, church, or other building, consisting of columns at regular intervals supporting a roof often in the form of a pediment.”
But “porticus” can also mean “a covered colonnade in this style,” according to the OED.
Another word that means the same thing is “portico,” which is more common than “porticus” and was adopted at about the same time.
We got “portico” from Italy, where it’s the Italian version of the Latin porticus.
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