TH

• Eth (ð), a letter used in Old English, Icelandic, Faroese and Elfdalian
• Th (digraph), a digraph in the Roman alphabet
  • Pronunciation of English th aspects of this digraph in English
  • Voiced dental fricative /ð/, a type of consonantal sound in some languages
  • Voiceless dental fricative /θ/, a type of consonantal sound in some languages
• Thai language (ISO 639 code), the national and official language of Thailand
• Thorn (letter) (þ), a letter in Old Norse, Old English, Icelandic and related languages
• "-th," the most common ordinal number suffix in English (in some style guides rendered ^th)

• Thuringia, a state of Germany
• Territory of Hawaii, formerly the Republic of Hawaii and prior to that the Kingdom of Hawaii
• Terre Haute, Indiana

Biology and medicine

• T helper cell Th, in the immune system
• Terminologia Histologica, an international standard for nomenclature in cytology and histology
• Thyroid hormones, in the endocrine system
• Tyrosine hydroxylase, an enzyme

Units of measurement

• Thomson (unit) (Th) in mass spectrometry
• Thermie (th), metric unit of heat energy equal to 1,000 kilocalories

Other uses in science and technology

• .th, the Internet country code top-level domain for Thailand
• Thorium, symbol Th, a chemical element
• Tianhe (space station module)
• <th>...</th>, HTML element for table header cell
• Hold time (t_h) of a flip flop in electronics

• Tommy Hilfiger, an apparel brand
• Taiwan Historica, an academic institution in Nantou County, Taiwan
• Technische Hochschule, a Technical University in German-speaking countries
• Technische hogeschool, a Technical University in Dutch-speaking countries
• Telegraph Herald, a newspaper in Dubuque, Iowa, USA, nickname
• Thai Airways Company (former IATA airline designator TH)
• Raya Airways, Malaysia (IATA airline designator TH)

• Thursday, abbreviated Th
• Th (album), a 1997 album by the Glenn Spearman–John Heward Group

• All pages with titles beginning with th