Labat is the twelfth letter of the Samaritan alphabet and carries the numeral value thirty. It writes a plain l. The name is the inherited Northwest Semitic one behind Hebrew lamed, glossed as an ox goad, a reading reconstructed from the word rather than recorded by anyone using the script.
Labat is the second of the three single letter prepositions, the one meaning to or for, and it is also the marker of the infinitive, so it stands at the front of an enormous number of words. In a text of any length it will be among the commonest letters on the page for grammatical reasons alone, before any question of the sounds of the language comes into it.
Greek took the sign as lambda, and Latin took it from Greek as L, both keeping the sound. The three letters look progressively less like one another the further along you go, which is the ordinary result of centuries of separate handwriting rather than any deliberate redesign. The sound and the position in the sequence stayed put while the shapes drifted.
The character is encoded at U+080B.
As a numeral labat is thirty, and it is one of the letters a reader meets often in a manuscript colophon, where a scribe writing out a year has to build the number from the letters available to him. The alphabet gives him nine units, nine tens and four hundreds and nothing else, so a date of any size is a small piece of arithmetic laid out in letters.
The consonant itself is among the most stable in the family. Where the throat letters have weakened in the Samaritan reading tradition and two others have shifted their sound entirely, l has moved nowhere. In a script where the interesting letters are the ones that changed, this is one of the ones that did not.