my

Etymology 1

From Middle English mi, my, apocopated form of min, myn, from Old English mīn (“my, mine”), from Proto-West Germanic *mīn, from Proto-Germanic *mīnaz (“my, mine”, pron.) (possessive of *ek (“I”)), from Proto-Indo-European *méynos (“my; mine”). Cognate with West Frisian myn (“my”), Afrikaans my (“my”), Dutch mijn (“my”), German mein (“my”), Swedish min (“my”). More at me.

det

1. First-person singular possessive determiner. See Appendix:Possessive.
   1. Belonging to me.
      I can't find my book.
   2. Associated with me.
      My seat at the restaurant was uncomfortable.
      Don't you know my name?
      I recognised him because he had attended my school.
   3. Related to me.
      My parents won't let me go out tonight.
      From what conſummate vertue I have choſe / This perfect Man, by merit call'd my Son, 1671, John Milton, “The First Book”, in Paradise Regain’d. A Poem. In IV Books. To which is Added, Samson Agonistes, London: […] J. M[acock] for John Starkey[…], →OCLC, lines 165-166, page 10
   4. In the possession of me.
      I have to take my books back to the library soon.

Etymology 2

An abbreviation of an oath such as my word or my Lord

intj

1. Used to express surprise, shock or amazement.
   My, what big teeth you have!