O say can you see … that this line begins with an “ O ” and not an “ Oh ” ? “ O ” may seem like just an onetime fashioned way to write “ Oh , ” but it really has a more or less different meaning . Consider some other famous type O ’s : O Captain , my police captain , O Pioneers , O issue forth All Ye close , O Canada , O Brother Where Art Thou , O ye of little faith , O Christmas Tree . These are all examples of what ’s known as the vocative oxygen — it indicates that someone or something is being directly addressed . When you say “ O Christmas Sir Herbert Beerbohm Tree ” the “ O ” means you are talking right to the Christmas tree . The residuum of the song bears this out . ( Your branches are lovely ! You ’re always wearing that dress of green ! ) Same for “ O Canada ” and somewhat much any hymn . The language to your school song plausibly go something like “ O [ alma mater ] , your campus is beautiful , and we think you ’re great . ”
“ Oh ” has a panoptic scope . It can indicate pain , surprise , disappointment , or really any emotional state . While “ oh , humankind ! ” could intend a telephone number of things , “ O man ! ” mean “ hey , you there … you man over there . ”
The convention now is that while “ oh ” can be down in the mouth case , and is normally followed by a comma , “ O ” is always uppercase and without a Polygonia comma . But there has n’t always been a strict detachment between the two forms . “ Oh ” and “ O ” were used interchangeably for a long sentence . The meanings often overlap too . When Juliet says , “ O Romeo , Romeo , wherefore nontextual matter thou Romeo ? ” is she address him in her imagination or sighing with emotion ? A little of both . It ’s not hard to see why it ’s so unmanageable to keep a firm border around vocative O in English . These days it looks jolly rarefied and archaic and is usually only reckon in old poem and vocal titles …
… ya , rly . Thanks to LOLspeak , " O " has find a way to adjust and survive , but there it ’s not limited to the vocative good sense . The versatile , nimble " O " rolls on its merry way , picking up Modern meanings , and endeavor to stay relevant however it can .
