Why is interesting sometimes pronounced as intra-sting? The same goes for interest sometimes being pronounced without the first e.
For the same reason "surprise" is frequently pronounced as "sah-prise": people sometimes take shortcuts if the meaning is still clear even with the mispronunciation. For more examples, see here, including this detailed explanation of the specific pronunciations of "interesting":
I believe this is called "linguistic conservation". This is why people in the north east refuse to pronounce R's; i.e. it's easier to say.
For example, what's harder to say: lie-berry or library? The first one is easier ergo linguistic conservation.
mispronunciations that annoy me are: lie-berry instead of library, supposably instead of supposedly, axed instead of asked etc
I still don't know why Texans put a T in across to get acrosst. I guess it's a substitution for -ed. But why would you need -ed there in the first place?
It's a case of Nature imposing the law of necessity and sufficiency on us. The missing vowel in question is not necessary for comprehending the word/concpt, but the remaining ones are, and so we have the situation you noted in numerous cases. These cases, of course, are a stumbling block for ESL students, and since I am an ESL teacher, I compiled a list of some of them (all I could conveniently get on one page). Here is the article:
Minimal Words with a
Silent Internal Isolated Vowel (SIIV)
in American English
Non-example 1: “ate” – the “e” is silent, but not internal.
Non-example 2: “seat” – the “a” is silent and internal, but not isolated.
Non-example 3: “promised” – the “e” is silent, internal, and isolated, but the word is not minimal – removing the “d” does not change the root meaning.
Non-example 4: “lineman” – the “e” is silent, internal, and isolated, but the word is not minimal, being a compound word.
Note: A siiv might be variable, as in “temperament”, which can be pronounced “temprament” or “temperment”.
Missing out a weakly stressed vowel in a word (as the first