1. Variant of terce.
2. A measure of liquid capacity, equal to a third of a pipe, or 42 gallons (159 liters).
3. Games A sequence of three cards of the same suit.
4. Sports The third position from which a parry or thrust can be made in fencing.
5. Music An interval of a third.
[Middle English, from Old French, from feminine of tiers, third, from Latin tertius; see trei- in the Appendix of Indo-European roots.]
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