Where does “mackerel sky” come from?

mackerel sky (English) comes from English mackerel, from Middle English makerel, from Old French maquerel, from Middle Dutch makelare, from Low German maken, from Middle Low German māken, from Old Saxon makōn, from Proto-West Germanic makōn — to oil, knead; to knead, oil.

mackerel sky (English): A sky filled with a regular pattern of altocumulus clouds somewhat resembling the skin of a mackerel

Definitions

  1. A sky filled with a regular pattern of altocumulus clouds somewhat resembling the skin of a mackerel

Ancestry of “mackerel sky”, step by step

mackerel sky traces back through two separate lines of ancestry.

via English mackerel

StepLanguageWordMeaning
1EnglishmackerelAn edible fish of the family Scombridae, often...
2Middle Englishmakerelmackerel
3Old Frenchmaquerelmackerel
4Middle Dutchmakelare
5Low GermanmakenTo make
6Middle Low Germanmāken
7Old Saxonmakōnto make
8Proto-West Germanicmakōnto build, work, make
9Proto-Germanicmakazfit, suitable, agreeable, comfortable
10Proto-Indo-Europeanmaǵ-to oil, knead; to knead, oil

via English sky

StepLanguageWordMeaning
1EnglishskyThe atmosphere above a given point, especially as...
2Middle EnglishskyThe atmosphere or sky; that which lies above the...
3Old Norseskýcloud
4Proto-Germanicskiwjącloud; sky
5Proto-Indo-European(s)kewH-to cover, bedeck; cover
Every word from Proto-Indo-European maǵ-Every word from Proto-Germanic makazEvery word from Proto-West Germanic makōn