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per·me·ate

(pûrmē-āt′)

v. per·me·at·ed, per·me·at·ing, per·me·ates

v.tr.

1. To pass through the openings or interstices of: liquid permeating a membrane.

2. To spread or flow throughout; pervade: "Our thinking is permeated by our historical myths" (Freeman J. Dyson). See Synonyms at imbue.

v.intr.

To spread through or penetrate something.

[Latin permeāre, permeāt-, to penetrate : per-, through; see PER- + meāre, to pass; see mei-¹ in the Appendix of Indo-European roots.]

perme·ant (-ənt), perme·a′tive (-ā′tĭv) adj.

per′me·ation n.

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:

Indo-European Roots

Semitic Roots

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.

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