пожалуйста

Etymology
Lexicalization of +, an obsolete clitic that was used to add emphasis and to signify politeness, of obscure origin. The clitic is no longer used or known to most speakers, even as passive vocabulary, and has essentially disappeared from the language. Accordingly, to modern speakers, the ending of the word пожалуйста is merely a sequence of sounds of indeterminate meaning.

The letter й, despite still being used in the spelling, was dropped from the pronunciation.

Interjection

 * 1) please
 * 2) you're welcome, not at all, don't mention it, it's a pleasure (reply to thank you)
 * 3) here you are (when handing something over)
 * 1) here you are (when handing something over)