6th

6th is the ordinal form of the number six, used to indicate position in a sequence. It is written as the numeral 6 followed by the suffix -th (6th). In English, most numbers take -th, with exceptions for 1, 2, and 3 (1st, 2nd, 3rd).

Common uses include dates and addresses (the 6th of January; 6th Avenue), floors or levels in buildings (the 6th floor), and ordered items (the 6th item on a list). It also appears in legal and formal references, such as the 6th Amendment to the United States Constitution.

In mathematics and science, '6th' denotes the ordinal rank six within a set. In astronomy, the 6th planet from the Sun is Saturn; in chemistry, the number six is the atomic number of carbon, though ordinals are not typically used to name elements.

In culture, the word 'sixth' appears in titles and names, as in "the Sixth Sense" or "Sixth Form" in parts of the UK, which refers to a stage of post-16 education. Street and district names such as "6th Street" and "6th Ward" are common in many cities.

Usage notes: when writing, '6th' is appropriate in informal contexts and on maps or signs; in formal prose, spelling out "the sixth" is often preferred, especially at the beginning of a sentence. Order and ranking contexts rely on the ordinal form to convey sequence.