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Learned borrowing from Old English seax (“dagger”). Doublet of sax and zax.

• IPA^(key): /ˈsiːks/, /ˈseɪ̯.æks/
• Rhymes: -iːks, -eɪæks
• Hyphenation: seax‧,‧se‧ax
• Homophone: seeks

seax (plural seaxes)

1. (historical) A short Saxon sword.

   • 1786, Francis Grose, A Treatise on Ancient Armour and Weapons, page 34:

     The Pugio or Dagger was used by the Romans, a species of that weapon called the Hand Seax was worn by the Saxons, with which they massacred the English on Salisbury Plain in 476.

   • 1950 June, Michael Robbins, “Heraldry of London Underground Railways”, in Railway Magazine, page 380:

     It consisted of the arms of the City of London, Middlesex (three seaxes, or Saxon swords), Buckingham (a swan), and Hertford (a hart), arranged quarterly, on a background of crimson and ermine mantling […] .

• Saxe, axes, sexa-

seax

1. (Early Middle English) alternative form of sax

• sex — West Saxon
• syx, sex

From Proto-West Germanic *sahs, from Proto-Germanic *sahsą. Compare Old English sagu, seċġ.

• IPA^(key): /sæ͜ɑks/

seax n

1. knife

   Synonym: (rare or dialectical) cnīf

Strong a-stem:

• lǣċeseax
• meteseax
• næġlseax
• sċierseax

• Seaxa

• Middle English: sax, sexe, sex, sæx, seax
  • English: sax; zax
  • Scots: saks; sax (verb) (through confluence with Norse form)
• → English: seax (learned)