Definition of ironclad. 1  1 : sheathed in iron armor âused especially of naval vessels. 2  2 : so firm or secure as to be unbreakable: such asa : binding an ironclad oathb : having no obvious weakness an ironclad case against the defendant.
Best Answer: CR means a credit. If this appears on the balance due line of your statement, it means that you owe nothing and that you are that much ahead of future charges and no payment or acknowledgment is needed.
CR stands for Cost Reimbursable (contract type). Suggest new definition. This definition appears frequently and is found in the following Acronym Finder categories: 1  Military and Government. 2  Business, finance, etc.amples in periodicals archive: The firm-fixed-price, cost reimbursable contract to support Afghanistan s national police force has a base period of nine months and two options that could extend the project up to six months and is worth up to $52.