• Third-class degree, in the British higher education system

In music theory:

• Major third or Minor third
• Mediant, the third degree of the diatonic scale

In musical works:

• Third/Sister Lovers, by Big Star
• Third (Soft Machine album)
• Third (Portishead album)

In dramatic works:

• Third (play), by Wendy Wasserstein

In literature:

• A third child permitted only by a special sanction of the government in Ender's Game, and are referred to as "Thirds"

See also

• 3rd or 3
• The Third (disambiguation)
• Ladder of thirds
• Third world