insure
verb
[with object]
1 arrange for compensation in the event of damage to or loss of (property), or injury to or the death of (someone), in exchange for regular payments to a company or to the state:the table should be insured for £2,500the company had insured itself against a fall of the dollar[no object] :businesses can insure against exchange rate fluctuations
secure the payment of (an amount in compensation) in this way:your new sum insured is shown on your renewal notice
provide insurance cover in respect of:subsidiaries set up to insure the risks of a group of companies
2 (insure someone against) secure or protect someone against (a possible contingency):by appeasing Celia they might insure themselves against further misfortune[no object] :such changes could insure against further unrest
3 another term for ensure
I will assume that your instruction to ask any "English major, or even a grade school teacher" is intended as an affront. Being not of thin skin, I will not permit a petty individual to beleaguer and bore me.
My comment was not meant as a snark, but a reference to the rather strict and unyielding rules of grammar drilled into me while attending St. Anthony’s School.
Common usages are often referenced in many modern dictionaries. Just because they are commonly used/misused/abused does not excuse the misapplication of words, even if it is common practice.
Look at what has happened to English in the inner city, and you will see where common misuse of words leads.
Perhaps it seems somewhat pedantic, and maybe it is, but it’s a personal peeve.
Have a good day either way.