To spell the word S-I-R in Spanish....S, I, R...the letters are exactly the same in Spanish, just pronounced differently....hehehe...sorry! I'm felling a little slap happy after doing 7 loads of laundry, changing all the bedding, cleaning the house top to bottom and grilling steaks for dinner. I'd swear if I was pregnant I'd be ready to pop out that baby any minute...nesting ya know.
Anyway, the equivalent word in Spanish for "sir" is Senor with a tilda (~) over the N.