What does the lower-case "e" symbol that appears on the front label of
some higher-end beauty products stand for? It's usually at the bottom
next to the net weight. Aveda, Shiseido and Lancome are examples of
products in which this symbol appears. Thanks!

Hello Bird66,

The "e" symbol  is the Estimated Sign

"The estimated sign (?) is a mark required to be appended to the
nominal mass or volume printed on prepackaged goods for sale within
the European Union. It certifies that the actual contents of the
package comply with specified criteria for estimation."

The "estimated" sign looks like a minuscule "e", and its shape is
precisely defined by an EU directive. This sign has been added to the
Unicode list of characters, just as the symbol for the Euro has been,
and can be considered a new basic character in a typeface. It is
character U+212E (?).

Read more here:
http://en.wikipedia.org/wiki/%22Estimated%22_sign

Large Image of the Estimated Sign
http://en.wikipedia.org/wiki/Image:Estimated_sign.png


"In legal metrology, the "estimated" sign (the symbol ?) following a
measurement of quantity (e.g., 750 ml ?) is used to indicate that the
measurement of weight or volume is done according to preset rules with
specific allowable variances."
Wikipedia
http://en.wikipedia.org/wiki/E

Search terms
weight ml e stands for 
stands for  "ml " "e stands for"

I hope this is helpful!

Best regards,
Bobbie7