| No. | Item | Definition |
|---|---|---|
| 1. | accuracy | how closely time is kept |
| 2. | acrylic | plastic crystal material |
| 3. | alarm | watch with audible alert |
| 4. | amplitude | swing angle of the balance |
| 5. | annual calendar | calendar adjusting most month lengths |
| 6. | automatic | self-winding mechanical watch |
| 7. | balance | oscillating wheel controlling rate |
| 8. | barrel | drum housing the mainspring |
| 9. | beat rate | oscillation frequency of the movement |
| 10. | bezel | the ring around the crystal |
| 11. | big date | oversized date display |
| 12. | bracelet | a metal watch band |
| 13. | bronze | alloy that develops patina |
| 14. | caliber | a specific movement model |
| 15. | case | the outer body of the watch |
| 16. | chapter ring | ring carrying minute or hour markers |
| 17. | chronograph | watch with stopwatch function |
| 18. | chronometer | certified high-accuracy watch |
| 19. | complication | any function beyond time display |
| 20. | crown | the knob for winding and setting |
| 21. | crystal | the transparent cover over dial |
| 22. | date window | aperture showing the date |
| 23. | day-date | display showing day and date |
| 24. | deployant | folding strap buckle |
| 25. | dial | the watch face |
| 26. | diver | watch designed for underwater use |
| 27. | DLC | hard black carbon coating |
| 28. | dress watch | simple formal watch style |
| 29. | ebauche | unfinished movement supplied to brands |
| 30. | escapement | mechanism regulating gear release |
| 31. | exhibition caseback | transparent back showing movement |
| 32. | field watch | rugged military-inspired watch |
| 33. | flyback | chronograph resets without stopping first |
| 34. | frankenwatch | watch assembled from mixed parts |
| 35. | full set | watch with box and papers |
| 36. | gain | time running fast |
| 37. | GMT | second time zone display |
| 38. | gold | precious metal used in watches |
| 39. | grail | dream watch to own |
| 40. | grey market | unofficial but legal sales channel |
| 41. | guilloche | engine-turned decorative pattern |
| 42. | hammer price | winning bid before fees |
| 43. | hands | pointers showing time |
| 44. | helium valve | valve releasing trapped helium |
| 45. | homage | design closely inspired by another |
| 46. | in-house | made by the brand itself |
| 47. | indices | hour markers on the dial |
| 48. | integrated bracelet | bracelet flowing into the case |
| 49. | jewel | synthetic bearing reducing friction |
| 50. | jump hour | hour display that changes instantly |
| 51. | limited edition | model made in fixed quantity |
| 52. | loom | glow-in-the-dark material |
| 53. | loss | time running slow |
| 54. | lubrication | application of movement oils |
| 55. | lug | case projection holding the strap |
| 56. | lume | glow-in-the-dark watch compound |
| 57. | mainspring | coiled spring storing power |
| 58. | manual-wind | mechanical watch wound by hand |
| 59. | mineral | hardened glass crystal material |
| 60. | minute repeater | watch that chimes the time |
| 61. | moonphase | display of lunar cycle |
| 62. | movement | the mechanism powering the watch |
| 63. | NOS | new old stock condition |
| 64. | originality | degree of factory-correct parts |
| 65. | overhaul | complete movement cleaning and repair |
| 66. | patina | aging that changes appearance |
| 67. | perpetual calendar | calendar accounting for leap years |
| 68. | pilot watch | aviation-oriented watch design |
| 69. | pin buckle | traditional tang-style buckle |
| 70. | platinum | dense precious metal for watches |
| 71. | power reserve | remaining running time indication |
| 72. | pulsometer | scale for measuring pulse rate |
| 73. | PVD | surface coating process |
| 74. | quartz | battery watch regulated by crystal |
| 75. | radium | older radioactive luminous material |
| 76. | rattrapante | split-seconds chronograph function |
| 77. | regulation | adjustment to improve timekeeping |
| 78. | regulator | separate displays for hours and minutes |
| 79. | rehaut | inner bezel around the dial |
| 80. | retrograde | hand snaps back after arc |
| 81. | rotor | swinging weight for self-winding |
| 82. | sapphire | hard synthetic crystal material |
| 83. | screw-down crown | threaded crown sealing the case |
| 84. | service | maintenance and overhaul work |
| 85. | slide rule | bezel scale for calculations |
| 86. | steel | common metal for watch cases |
| 87. | strap | a nonmetal watch band |
| 88. | subdial | small dial within the main dial |
| 89. | Super-LumiNova | common luminous dial material |
| 90. | tachymeter | scale for measuring speed |
| 91. | telemeter | scale for measuring distance |
| 92. | titanium | light strong metal for cases |
| 93. | tool watch | watch built for practical use |
| 94. | tourbillon | rotating escapement to reduce errors |
| 95. | tritium | radioactive luminous material once used |
| 96. | unpolished | retaining original case lines |
| 97. | vph | vibrations per hour |
| 98. | waitlist | queue for a hard-to-get watch |
| 99. | water resistance | ability to resist water entry |
| 100. | worldtimer | watch showing multiple time zones |
