| lesser of two evils | | | |
| let a sleeping dog lie | | | |
| let crazy stick its dick in you | | | |
| let drive | | | |
| let go and let God | | | |
| let it alone | | | |
| let loose | | | |
| let nature take its course | | | |
| let on | | | |
| let oneself go | | | |
| let-out | | | |
| let's get the party started | | | |
| let sleeping dogs lie | | | |
| let slip | | | |
| let someone have it | | | |
| let the cat out of the bag | | | |
| let the perfect be the enemy of the good | | | |
| let well alone | | | |
| level to the ground | | | |
| lick and a promise | | | |
| lick one's chops | | | |
| lick someone's balls | | | |
| lie before | | | |
| lie through one's teeth | | | |
| life of Riley | | | |
| lift all boats | | | |
| light at the end of the tunnel | | | |
| lighten up | | | |
| lightning in a bottle | | | |
| light skirt | | | |
| light the blue touchpaper | | | |
| like a champ | | | |
| like a duck to water | | | |
| like cheese at fourpence | | | |
| like one's life depended on it | | | |
| like there is no tomorrow | | | |
| line in the sand | | | |
| line one's pockets | | | |
| linger on | | | |
| lion's den | | | |
| liquid courage | | | |
| little hand | | | |
| little old | | | |
| live and let live | | | |
| live in sin | | | |
| live off | | | |
| live on the edge | | | |
| live the dream | | | |
| live with | | | |
| loaded language | | | |
| load up | | | |
| locker room humor | | | |
| lock someone up and throw away the key | | | |
| long arm | | | |
| long drink | | | |
| long in coming | | | |
| long pork | | | |
| long since | | | |
| long-time listener, first-time caller | | | |
| look as if one has lost a shilling and found sixpence | | | |
| look down one's nose | | | |
| look here | | | |
| look off | | | |
| look out | | | |
| look over one's shoulder | | | |
| look up | | | |
| look what the cat's dragged in | | | |
| loose lip | | | |
| loosen the apron strings | | | |
| lord of the flies | | | |
| lose face | | | |
| lose one's bottle | | | |
| lose one's mind | | | |
| lose one's tongue | | | |
| lose patience | | | |
| lose the plot | | | |
| lost errand | | | |
| lost to the world | | | |
| love away | | | |
| love muscle | | | |
| lower one's sights | | | |
| low-lying | | | |
| lubrication payment | | | |
| lucky break | | | |
| lucky star | | | |
| lunchbox | | | |
| L in the chat | | | |
| lionhearted | | | |
| listen up | | | |
| little girl | | | |
| little pitcher | | | |
| live and die by | | | |
| live in the past | | | |
| live large | | | |
| live over the brush | | | |
| live rent-free in someone's mind | | | |
| living death | | | |
| loaded for bear | | | |
| load up on | | | |
| locked up | | | |