A common way to identify oneself.

(idiomatic) Indicates disapproval, disregard, disdain, disgust or disbelief. / Used other than figuratively or idiomatically: see my, foot.

(colloquial, idiomatic) My fault; mea culpa.

Alternative form of oh my God

(chiefly US, euphemistic) my God

(idiomatic) Expression of disapproval, disregard, disdain, disgust, or disbelief.

(idiomatic) Do as you wish; go ahead; help yourself; go for it!

(slang, British, vulgar) Indicates incredulous disapproval, contradiction or disbelief.

(US, Canada, minced oath) Used to express surprise, shock, or amazement.

(idiomatic, Australia, New Zealand, UK, dated, US, Canada) An expression of surprise. / (idiomatic, Australia, New Zealand, UK, dated, US, Canada) Indeed.