sac·cade (să-käd, sə-)
A rapid intermittent eye movement, as that which occurs when the eyes fix on one point after another in the visual field.
[French, jerk, jolt, from Middle French, from Old French dialectal saquer, to jerk, pull, variant of Old French sachier, to pull forcefully, turn over, shake up, from sac, sack (perhaps in reference to the shaking of bags of wheat to settle their contents); see SAC1.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.