Can someone please give me an easy to understand definition of status post?

"Status post" (abbreviated s/p, as you note) is just medicalese for "the patient had a (X)" (at some point in the past) -- her/his status is post-(whatever the specified procedure is).

"S/p tracheostomy" just means that your patient has had a tracheostomy; "s/p L BKA" would mean that the patient has had a left below the knee amputation, etc., etc. "S/p" notations in the diagnosis or admit notes are usually used not to note the person's entire medical history, but to highlight the most recent acute medical problems and chronic conditions (like a tracheostomy, mastectomy, missing organs, etc.) that everyone needs to know about up front because they impact the patient's care/treatment of whatever the current/acute problem is.

I found both words in my copy of Taber's which is an 18th edition. Status and post are listed separately in the main listings. Both are latin words. Status meaning condition; post meaning after. Put together they would mean condition after. Try looking again. I can't think why they would have deleted them since this book gets thicker all the time.

In my Taber's, "post" is listed in the "P's" between "Possum" and "postabortal" on page 1531. If you have a different edition, the page numbers will be different. "Status" is on page 1826 in the "T's" between the words "stature" and "statute".