τρίτο

In a sentence

• Είναι το τρίτο σπίτι από αριστερά.

  It is the third house from the left.

  Here 'τρίτο' is used as an ordinal number, indicating position in a sequence.

• Το τρίτο πρόβλημα ήταν το πιο δύσκολο.

  The third problem was the hardest.

  In this sentence, 'τρίτο' functions as an adjective, describing which instance of the noun (problem) was being discussed.

• Παράγγειλα το τρίτο ποτήρι καφέ για σήμερα.

  I ordered the third cup of coffee for today.

  Here, 'τρίτο' refers to the order of an event or an item in a daily routine or consumption.