Definition of Welsh onion in English:

Welsh onion

noun

  • An Asian onion that forms clusters of slender bulbs which resemble salad (spring) onions. It is the onion most commonly used in SE Asia.

    Allium fistulosum, family Liliaceae (or Alliaceae)

    • ‘The Welsh onions are now in the unheated sun room; the petunias are in the house as they need warmer temperatures to germinate.’
    • ‘They've got some unusual things growing there - Welsh onions are a perennial onion which grows in clumps.’
    • ‘Sunday was a quieter day, garden-wise, but I did manage to pot up my 5 sweetcorn plants and I also planted up my strawberry tower with 11 petunias, 5 basil, 4 carrots and 4 Welsh onions.’
    • ‘Now there should be room for the 5 sweetcorn (which are growing well) and the sprouting broccoli and the 4 runner beans I have been given in exchange for the Welsh onions.’
    • ‘In the cold frame outside the beans, peas Welsh onions and sweet peas are also doing well, and I'm now leaving the lid open all the time.’

Origin

Early 18th century (as Welch onion): Welsh from German welsch ‘foreign’.