This is the 6222nd most frequent Russian word.
третьи
"Третьи" means "third" (plural form) in English.
In this usage, 'третьи' denotes the ordinal number modifying 'сутки' (days), indicating sequence.
Третьи сутки идут проливные дожди.
The third day continuous rains are ongoing.
Here, 'третьи' refers to the ordinal number qualifying 'ворота' (gate), pointing to its position in a sequence of gates.
Третьи ворота были закрыты.
The third gate was closed.
In this case, 'третьи' acts as a descriptor indicating sequence, applied to 'работы' (works).