名詞 hallmark:

1. a distinctive characteristic or attribute
   同義詞：trademark, earmark, stylemark
2. a mark on an article of trade to indicate its origin and authenticity
   同義詞：authentication, assay-mark

1. The plan has all the hallmarks of being a total failure.
   這個方案具有徹底失敗的一切標志。
2. Attention to detail is the hallmark of a fine craftsman.
   能工巧匠的特點是一絲不茍。

hall.mark

n.（名詞）
A mark indicating quality or excellence.
純正標記：一種指明質量或品質的標記
A mark used in England to stamp gold and silver articles that meet established standards of purity.
純度標記：用于英國的標在金、銀制品上的同設立的純度標準相符的標記
A conspicuous feature or characteristic:
標志：顯而易見的特點或特征：
例句：
.The sense of guilt is the hallmark of civilized humanity.(Theodor Reik)
.犯罪感是文明人顯而易見的特征.(西奧多·賴克)

v.tr.（及物動詞）
hall.marked,hall.mark.ing,hall.marks
To stamp (gold and silver articles) with a mark indicating purity.
標純度：給（金、銀制品上）標上指明純度的標記

來源：
After Goldsmith`s Hall in London, England, where gold and silver articles were appraised and stamped
源自金匠的 會堂 ，位于英格蘭倫敦，在此對金銀物品進行鑒定和做標記