# primer

Pronunciation: US say "PRY-mur" /ˈpɹaɪmɚ/; UK say "PRY-muh" /ˈpɹaɪ.mə(ɹ)/

## Noun

1. A preparatory coating applied to wood, metal, or other surfaces before painting.
   - Simple: A first coat of paint that helps the top color stick to wood or metal.
   - _Apply primer to the bare drywall before the first coat of color._
   - _Galvanized steel requires a special primer to keep the paint from flaking._
2. An introductory text on a subject, covering its basic concepts. (pronounced: US say "PRIM-ur" /ˈpɹɪm.ɚ/; UK say "PRY-muh" /ˈpɹaɪ.mə(ɹ)/)
   - Simple: A simple book or text that teaches the basics of a subject.
   - _The professor wrote a primer on quantum computing for nonspecialists._
   - _Several primers on climate science are aimed at general readers._
3. A substance or device, such as a blasting cap or priming wire, used to ignite gunpowder or another explosive.
   - Simple: A small device or material that sets off gunpowder or other explosives.
   - _Each round relies on a primer to ignite the propellant charge._
   - _Demolition crews insert a primer to detonate the main explosive._
4. A children's book designed to teach the basics of reading, writing, and spelling. (pronounced: US say "PRIM-ur" /ˈpɹɪm.ɚ/; UK say "PRY-muh" /ˈpɹaɪ.mə(ɹ)/)
   - Simple: A child's first book for learning to read, write, and spell.
   - _Generations of students learned to read from the same well-worn primer._
   - _The classroom shelf held a stack of primers for the youngest pupils._
5. A base layer of makeup worn beneath the foundation to smooth the skin.
   - Simple: A makeup layer you put on before foundation to help it go on smoothly.
   - _A silicone-based primer fills fine lines before the foundation is applied._
   - _He patted primer over his nose to keep the shine down._
6. A single layer of the preparatory coating applied before the finish paint.
   - Simple: One coat of the base paint that goes on before the top color.
   - _The painter applied a primer, then sanded it lightly before the topcoat._
   - _Two thin primers adhere better than one thick coat._
7. A molecule that initiates the synthesis of an enzyme, especially a short single-stranded nucleic acid that starts DNA replication.
   - Simple: A small molecule that helps start the copying of DNA.
   - _The technician added a primer that binds to the target sequence before amplification._
   - _Short primers anneal to the template strand to begin replication._
8. A device that injects gasoline into an internal combustion engine to help it start, especially in airplanes.
   - Simple: A small pump or device that feeds gasoline into an engine to help it start.
   - _He pumped the primer twice to flood the cylinders with fuel before ignition._
   - _Aircraft mechanics check that the primer seals properly to prevent fuel leaks._
9. In biology, a pheromone that acts first on the hormone-producing endocrine system of the animal that receives it.
   - Simple: A natural scent signal that acts on the body's hormone system.
   - _A queen bee releases a primer that suppresses ovary development in workers._
   - _Mammalian primers can alter reproductive cycles in nearby individuals._
10. Someone who prunes trees, cutting away branches to shape them or keep them healthy.
   - Simple: A person whose job is trimming and cutting back trees.
   - _The estate hired a primer to thin out the old apple trees._
   - _Skilled primers know exactly which limbs to remove without harming the tree._
11. A devotional book for laypeople, originally a shortened breviary containing the hours of the Virgin Mary, the penitential psalms, the litany, and the office of the dead. (pronounced: US say "PRIM-ur" /ˈpɹɪm.ɚ/; UK say "PRY-muh" /ˈpɹaɪ.mə(ɹ)/)
   - Simple: A prayer book for ordinary people, used for private worship long ago.
   - _The widow read from her primer each evening by candlelight._
   - _Illuminated primers were treasured possessions in medieval households._
12. Any of various English books issued for private prayer in accordance with the Book of Common Prayer. (pronounced: US say "PRIM-ur" /ˈpɹɪm.ɚ/; UK say "PRY-muh" /ˈpɹaɪ.mə(ɹ)/)
   - Simple: A small English prayer book for praying at home, based on the Book of Common Prayer.
   - _The family owned a worn primer they used for daily devotions at home._
   - _Several primers were printed in London during Elizabeth's reign._

## Noun

13. A worker who prepared explosive charges for detonation, fitting them with fuses or detonators. *(obsolete)*
   - Simple: A worker who prepared explosives so they would go off.
   - _The quarry's primer packed each charge and set the fuse by hand._
   - _An experienced primer could ready a blast in minutes._
14. A worker who applies a first, sealing coat to wood, metal, and similar surfaces before finish coats are added. *(obsolete)*
   - Simple: A worker who puts the first coat of paint on wood or metal.
15. A beginning class in an elementary school, or a young pupil belonging to it. *(obsolete, New Zealand)* (pronounced: US say "PRIM-ur" /ˈpɹɪm.ɚ/; UK say "PRY-muh" /ˈpɹaɪ.mə(ɹ)/)
   - Simple: A beginner class in a school, or a young child in that class.
   - _Each morning the primer recited the alphabet before the older children arrived._
   - _The youngest primers struggled to hold their slates steady._

## Adjective

16. First in time; initial or earliest. *(obsolete)*
   - Simple: Happening first, before anything else.
   - _The primer accounts of the voyage differ from later retellings._
   - _During the colony's primer days, supplies ran dangerously low._
17. First in importance; chief or premier. *(obsolete)*
   - Simple: Most important, or first in rank.
   - _The primer noble of the realm advised the king directly._
   - _His primer concern was the safety of the city._
18. First in position; foremost or at the front. *(obsolete)*
   - Simple: First in place, at the very front.
   - _The primer column advanced toward the gate._
   - _He took the primer seat at the long table._

## Origin

**Meanings 2, 4, 11–12, 15** — From Middle English primer, from Medieval Latin primarius and primarium ("prayer book"), possibly through Anglo-Norman primer, based on prima (the liturgical hour) plus the suffixes -arius and -arium. Its use for schoolbooks grew out of the late medieval and early modern practice of using such prayer books to teach reading.
**Meanings 1, 3, 5–10, 13–14** — Formed from prime plus the suffix -er.
**Meanings 16–18** — From Anglo-Norman primer ("first"), from Latin prīmārius ("first").

Source: DictionaryAI, https://dictionaryai.com/define/primer (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).