Swath - swathe

The spellings swath and swathe, in the more common of the two current homographs of swathe, are interchangeable in writing.

• • OED notes "Evidence is not available for determining the date of the appearance of the form with a long vowel typically represented by the spelling swathe (IPA: /sweɪð/), since in the early periods swathe , swathes , are phonetically ambiguous; in modern local use, swathe is characteristic of the northern counties; its use in literature has probably been furthered by association with [the second meaning of swathe (below)]." LPD distinguishes between the pronunciations:
    • swath has the vowel of 'got' and 'odd', IPA: /ɒ/ or that of 'north' and 'awe',/ɔ:/ (these are the British pronunciations given in OED 1989, which treats the pronunciations of both spellings the same).
    • swathe has the vowel of 'say' and 'day', IPA: /eɪ/.
  • The word, however spelled or pronounced, means literally 'a row [of wheat or hay, etc] left by one sweep of a scythe [in hand-mowing]'. It has been much extended in figurative meanings: some in a visual comparison, such as the swathes of dead troops 'mown down' by machine-guns, or the strips of damaged buildings left by bombing; or more metaphorically 'an area of confusion or damage [in any field]', such as 'the blizzard left a swath of immobilized vehicles across the city'; 'the Minister's change of policy left a swathe of disenchanted colleagues in the Party'. The [Cambridge Dictionary, 2021] added "a large part of something that includes several different things", citing in evidence "These people represent a broad/wide swathe of public opinion."

• The second current homograph swathe (which is not found as 'swath') can be a verb or a noun. The noun denotes 'a strip of cloth or similar' in which something is wrapped, specifically a bandage, or, archaically, swaddling clothes - the soft blanket in which a baby is wrapped; the verb 'to swathe' means 'to wrap up [a baby] in such a blanket'. (The synonym swaddling is often used in versions of the story of the birth of Jesus, and in the hymn 'Away in a Manger', the phrase "all meanly wrapped in swathing bands" (alternatively "swaddling bands"), may illustrate the nature of the child's garment.)

The fact that both swathes refer to 'strips' may lead one to hypothesize that they are the same word.

Do not confuse swathe (or swath) with swatch, as has been done.