Querent - The person a reading is being done for, so-called because they are asking the questions.
Spread - The layout of the cards in a reading.
Reader - The person responsible to analyzing and interpreting the cards in a reading.
Significator - A card chosen to represent an individual in a reading. Check out this post for several methods you can use to find yours.
Triplicity - Pertaining to three parts of one whole. For example, severity/mildness/mercy or Father/son/holy ghost. Also refers to three zodiac signs of the same element, as in how Scorpio, Pisces and Cancer are all water signs.
Zodiac Method - A method of selecting a significator for a person based on their astrological sign: pentacles for an earth sign, cups for a water sign, swords for an air sign, and wands for a fire sign. The type of court card is dependent on maturity and gender: princess/page or knight for younger individuals; queen or king for older individuals. Gender is up for interpretation.