Antonyms of adj 3rd

1 sense of 3rd

Sense 1
third, 3rd, tertiary -- (coming next after the second and just before the fourth in position)

INDIRECT (VIA ordinal) -> cardinal -- (being or denoting a numerical quantity but not order; "cardinal numbers")

Similarity of adj 3rd

1 sense of 3rd

Sense 1
third, 3rd, tertiary -- (coming next after the second and just before the fourth in position)
       => ordinal (vs. cardinal) -- (being or denoting a numerical order in a series; "ordinal numbers"; "held an ordinal rank of seventh")