Definition of "f-stop" [f-stop]

• A camera lens aperture setting that corresponds to an f-number. (noun)
• See f-number. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Notice the decrease in sharpness as I increased the f-stop (decreased the aperture diameter)."
• "Few of God's wonders are as inspiring as a waterfall: Ah ... wide-angle lens, 1/8-second exposure (without a tripod), f-stop, let's see ..."
• "Buy a camera that goes down to an f-stop of at least 2.8."