1. [n]  the 12th letter of the Roman alphabet
2. [n]  a cgs unit of illumination equal to the brightness of a perfectly diffusing surface that emits or reflects one lumen per square centimeter
3. [n]  a metric unit of capacity equal to the volume of 1 kilogram of pure water at 4 degrees centigrade and 760 mm of mercury (or approximately 1.76 pints)
4. [n]  the cardinal number that is the product of ten and five
5. [adj]  being ten more than forty

L
L

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1. \L\ ([e^]l).
   1. L is the twelfth letter of the English alphabet, and a
      vocal consonant. It is usually called a semivowel or
      liquid. Its form and value are from the Greek, through the
      Latin, the form of the Greek letter being from the
      Ph[oe]nician, and the ultimate origin prob. Egyptian.
      Etymologically, it is most closely related to r and u; as
      in pilgrim, peregrine, couch (fr. collocare), aubura (fr.
      LL. alburnus).
   Note: At the end of monosyllables containing a single vowel,
         it is often doubled, as in fall, full, bell; but not
         after digraphs, as in foul, fool, prowl, growl, foal.
         In English words, the terminating syllable le is
         unaccented, the e is silent, and l is preceded by a
         voice glide, as in able, eagle, pronounced [=a]"b'l,
         ?"g'l. See Guide to Pronunciation, [sect] 241.
   2. As a numeral, L stands for fifty in the English, as in the
      Latin language.
            For 50 the Romans used the Chalcidian chi, ?, which
            assumed the less difficult lapidary type, ?, and was
            then easily assimilated to L.         --I. Taylor
                                                  (The
                                                  Alphabet).
   

2. \L\ ([e^]l), n.
   1. An extension at right angles to the length of a main
      building, giving to the ground plan a form resembling the
      letter L; sometimes less properly applied to a narrower,
      or lower, extension in the direction of the length of the
      main building; a wing. [Written also {ell}.]
   2. (Mech.) A short right-angled pipe fitting, used in
      connecting two pipes at right angles. [Written also
      {ell}.]
   

3. \L\, a.
   1. Having the general shape of the (capital) letter L; as, an
      L beam, or L-beam.
   2. Elevated; -- a symbol for {el.} as an abbreviation of
      elevated in elevated road or railroad. -- n. An elevated
      road; as, to ride on the L. [Colloq., U. S.]