| L. | Fifty (Roman); Lake; Latin; learner (motoring); left; Liberal; lira or lire. |
| £ | Libra (Latin), pound(-s) (money). |
| 1. | Large; length; line; link(-s) (measure); litre(-s). |
| La. | Louisiana. |
| L.A. | Law agent; local authority. |
| £A. | Australian pound(-s). |
| la. | Last(-s) (weight). |
| Lab. | Labour; Labrador. |
| lab. | Laboratory. |
| Lam. | Lamentations of Jeremiah. |
| Lancs. | Lancashire. |
| Lat. | Latin. |
| lat. | Latitude; latrine. |
| lb. | Libra (Latin), pound(-s) (weight). |
| l.b. | Leg-bye(-s). |
| l.b.w. | Leg before wicket. |
| L.C. | Left of centre (stage); level crossing. |
| l.e. | Letter of credit; locus citatus (Latin), the passage mentioned; lower case (type). |
| l/c. | Letter of credit. |
| L.C.M. | Least common multiple. |
| L.D | La us Deo (Latin), praise be to God; Low Dutch. |
| L.E. | Labour exchange. |
| £E. | Egyptian pound(-s). |
| Leg. | Legation. |
| leg. | Legal; legato (Italian), smoothly. |
| Leics. | Leicestershire. |
| Lev(it). | Book of Leviticus. |
| L.G. | Lloyd-George (1st Earl); Low German; The London Gazette. |
| L.Gr. | Low Greek. |
| L.H. | Left hand. |
| Lib. | Liberal; librarian; library. |
| Lines. | Lincolnshire. |
| liq. | Liquid. |
| Lit. | Literature; Little. |
| lit. | Literal(-ly); litre. |
| Lit. Hum. | Literae Humaniores (Latin), Oxford examination in classics. |
| LL. | Laws. |
| L.L. | Late, or low Latin; Lend-Lease. |
| L.M. | Long measure (music). |
| L.M.S.(R.). | London. Midland. and Scottish Railway. |
| L.N.E.R. | London and North-Eastern Railway. |
| loc. cit. | Loco citato (Latin), at the place mentioned. |
| log(-s). | Logarithm(-s). |
| Lon. | London. |
| long. | Longitude. |
| loq. | Loquitur (Latin), he speaks. |
| L.P | Long primer; low pressure. |
| L.P.O. | London Philharmonic Orchestra. |
| L.P.T.B. | London Passenger Transport Board. |
| Lr. | Lower. |
| L.S. | Locus sigilli (Latin), the place of the seal. |
| L.S.C. | Lower School Certificate. |
| L.s.d. | Librae, solidi, denarii (Latin), pounds, shillings, and pence. |
| L.S.E. | London School of Economics. |
| L.S.O. | London Symphony Orchestra. |
| L.S.T. | Local standard time. |
| L.T. | Line telegraphy; London Transport; low tension. |
| £T | Turkish pound(-s). |
| It. | Light (adjective). |
| Ltd. | Limited. |
| L.U.E. | Left upper entrance. |
| Luth. | Lutheran. |
| L.V. | Last vehicle; Licensed Victuallers. |
| L.W. | Long wave. |
| L.W.L. | Load water line. |
| L.W.M. | Low water mark. |
| LXX. | The Septuagint. |