Engineering drawing abbreviations and symbols are used to simplify technical drawings and ensure clear communication between designers, engineers and manufacturers. Standardised systems such as BS 8888 define commonly used abbreviations for dimensions, features and notes.
Engineering drawing abbreviations and symbols are used to simplify technical drawings and ensure clear communication between designers, engineers and manufacturers. Standardised systems such as BS 8888 define commonly used abbreviations for dimensions, features and notes.
Abbreviations are used in engineering drawings to reduce space and improve clarity. They allow complex terms such as dimensions, features and manufacturing instructions to be communicated efficiently.
The following table lists standard abbreviations and symbols used in engineering drawings, including dimensional references, machining features and geometric terms.
The abbreviations below are based on common usage within BS 8888 and related engineering standards. These symbols are widely used in mechanical and manufacturing drawings.
| Term | Abbreviation or Symbol |
| Across Flats | AF |
| Assembly | ASSY |
| Centres | CRS |
| Centre Line ..On View |  |
| Centre line ..On Note | CL |
| Centre Of Gravity | CG |
| Chamfer of Chamferred..In a Note | CHAM |
| Cheese Head | CH HD |
| Countersunk/ Countersink | CSK |
| Countersunk Head | CSK HD |
| Counterbore | CBORE |
| Cylinder or Cylinderical | CYL |
| Diameter..in a note | DIA |
| Diameter..preceding a dimension |  |
| Drawing | DRG |
| Equally Spaced | EQUI SP |
| External | EXT |
| Figure | FIG |
| Full Indicated Movement | FIM |
| Hexagon | HEX |
| Hexagon Head | HEX HD |
| Insulated or Insulation | INSUL |
| Internal | INT |
| Least Material Condition..In a Note | LMC |
| Least Material Condition..(Geom.Dim) |  |
| Left hand | LH |
| Long | LG |
| Machine | MC |
| Material | MAT |
| Maximum | MAX |
| Maximum Material Condition..In a note | MMC |
| Maximum Material Condition..(Geom. tol) |  |
| Minimum | MIN |
| Not to Scale (In a note and underlined | NTS |
| Number | NO. |
| Pattern Number | PATT NO. |
| Pitch Circle Diameter | PCD |
| Radius..In a note | RAD |
| Radius..Preceding a dimension | R |
| Reference | REF |
| Required | REQD |
| Right hand | RH |
| Round Head | RD HD |
| Screw of Screwed | SCR |
| Sheet (Drawing Number) | SH |
| Sketch (prefix to Drawing Number) | SK |
| Specification | SPEC |
| Spherical Radius..Preceding dim | SR |
| Spotface | SFACE |
| Square ..In a note | SQ |
| Square ..Preceding dim |  |
| Standard | STD |
| Taper.. On Dia or Width |  |
| Thread | THD |
| Thick | THK |
| Tolerance | TOL |
| Typically OR Typical | TYP |
| Undercut | UCUT |
| Volume | VOL |
See related pages covering dimensioning methods, surface finish symbols and process flow diagram symbols used in engineering drawings.
Engineering drawing abbreviations are standardised shorthand terms used to represent dimensions, features and instructions on technical drawings.
They reduce space, improve clarity and allow complex information to be communicated efficiently.
Standards such as BS 8888 define commonly used abbreviations and symbols in engineering drawings.
PCD stands for Pitch Circle Diameter, commonly used to define bolt circle dimensions.
TYP means “typical” and indicates that a dimension or feature applies to multiple similar locations.