Definition of 'snow-in-summer'

Noun

1. annual spurge of western United States having showy white-bracted flower clusters and very poisonous milk
      Synonyms: snow-on-the-mountain ghost weed Euphorbia marginata
2. chickweed with hairy silver-grey leaves and rather large white flowers
      Synonyms: love-in-a-mist Cerastium tomentosum

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