Terran

Terran was a word used to refer to anything attributed to Humans or the planet Earth, which in Latin is Terra. The Klingonese word for Human is "tera'ngan". 

Usage when referring to things attributed to Humans:
 * "Terran" was used explicitly to refer to Humans...
 * ...in 2268, when a female Romulan Commander asked Spock if he called himself Terran or Vulcan.
 * ...in 2287, when Ambassador St. John Talbot was referred to as a Terran by both the Vulcan Sybok and the Klingon Vixis.
 * The SS Mariposa used a Terran distress beacon created by the European Hegemony.
 * Data referred to Terran conjugal rites.
 * Shinzon saw a Romulan doctor who had experience in Terran illnesses.

Usage when referring to things attributed to Earth:
 * The "Terran solar system" and "Terran system" were alternate names for the Sol system, which contained Earth.
 * The term Terran leech was used to separate it from other leeches.

Terran