latchkey

n key of an outer door, esp the front door of a house or flat 钥匙.

Las Vegas, lasagne (also lasagna), Lascar, lascivious, lasciviously, lasciviousness, laser, lash, lashing, lass, lassitude, lasso, last, last but not least, last name, last will and testament, lasting, lastly, lat, latch, latchkey child, late, latecomer, lately, latency, latent, latent heat, latent image, latent period, later, lateral, lateral thinking, laterite, latest, latex, lath, lathe, lather, Latin, Latin America,