Tierce

The tierce is an old English unit of wine casks, holding about 159 litres. From 1824 on it was defined by English law to be 35 imperial gallons, before that (and still in the USA) it was 42 wine gallons—the difference being less than tenth of a percent. It is closely related to the modern petrol barrel.
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Noun
1. the third canonical hour; about 9 a.m.
(synonym) terce
(hypernym) canonical hour
2. the cardinal number that is the sum of one and one and one
(synonym) three, 3, III, trio, threesome, leash, troika, triad, trine, trinity, ternary, ternion, triplet, tercet, terzetto, trey, deuce-ace
(hypernym) digit, figure
3. one of three equal parts of a divisible whole; "it contains approximately a third of the minimum daily requirement"
(synonym) one-third, third
(hypernym) common fraction, simple fraction

n. third; tierce

n. system of forecast betting giving first three horses

(n.)
The third tone of the scale. See Mediant.
  

(n.)
The third hour of the day, or nine a. m,; one of the canonical hours; also, the service appointed for that hour.
  

(n.)
A sequence of three playing cards of the same suit. Tierce of ace, king, queen, is called tierce-major.
  

(n.)
A position in thrusting or parrying in which the wrist and nails are turned downward.
  

(n.)
A cask whose content is one third of a pipe; that is, forty-two wine gallons; also, a liquid measure of forty-two wine, or thirty-five imperial, gallons.
  

(n.)
A cask larger than a barrel, and smaller than a hogshead or a puncheon, in which salt provisions, rice, etc., are packed for shipment.
  

(a.)
Divided into three equal parts of three different tinctures; -- said of an escutcheon.
  

Third canonical hour , approximately 9 am.