It happens a lot. People refer to the aperture being small (or big!). By default does this imply a small opening of the iris (literal aperture), or a small f-value (how the aperture is measured, for which the value gets bigger as the iris gets smaller)?
Answer
Unless there's further context about physical size, "small aperture" almost always means a higher f-number. This is also, of course, a smaller physical size for a given lens relative to wider apertures.
A small aperture means a high f number, like f/22 or f/32. Where one draws the line is open to interpretation, and to context. A small aperture is also called slow (because it lets in less light, requiring a longer shutter speed to compensate).
This means that a "smaller f-number" where the number is low is a larger aperture, not a smaller one. That's a bit confusing, so really it's better to avoid "small" and "large" (or "high" and "low") altogether and talk about "fast" and "slow".
Here's a quick aperture "cheat sheet":
(Note that the maximum "wide open" aperture will vary based on each lens design. f/2.8 is common for high-end zooms and f/3.5 to f/5.6 for cheap ones. Many prime lenses are faster. At the other end, most lenses for APS-C or 35mm stop down to f/22 or f/32.)
Charts like the one above used to come with cameras, usually along with suggestions for lighting conditions appropriate for each. But these days with instantly-variable digital ISO (rather than swapping film), and with point and shoot cameras just doing everything automatically, it's left for intermediate photographers and above. If you want to progress beyond point and shoot, though, familiarity with this scale remains important.
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