To pore over something is to study it closely and at length — poring over the accounts. To pour is to make a liquid flow. "Pouring over a document" is the frequent slip and produces an unintentionally wet image. Pore is also a noun: a tiny opening in the skin.
The core difference
Homophones, and one of them appears in a fixed phrase that is constantly misspelled.
- pore over — examine closely: she pored over the manuscript.
- pour — cause liquid to flow: pour the tea.
- pore (noun) — a small opening: blocked pores.
The phrase to watch
Pore over is the only common use of the verb, and because it appears almost exclusively in that phrase, many writers have only ever heard it. That is why pour over reaches print so often — and why coffee equipment now genuinely called a "pour-over" adds a further complication.
Related phrase
Pore over means to read closely; pour over is what you do to a pour-over coffee. Both exist, which is why the error survives spellcheck.
Frequently asked questions
Is it "pore over" or "pour over" a book?
Pore over. Pour involves liquid.
Is pore a noun as well?
Yes — a tiny opening in the skin or a surface.
Why is this mistake so common?
Because pore as a verb appears almost only in the phrase "pore over", so many writers have heard it without seeing it written.