Here, from EDGAR, are instances of obligations being referred to as irrevocable:
“Reimbursement Obligation” means the absolute, unconditional, and irrevocable obligation of the Borrower to reimburse the Issuing Bank for any drawing honored by the Issuing Bank under a Letter of Credit.
The obligation of Borrower to make payments hereunder and to observe and perform all of its other obligations under this Agreement are (subject to the terms of this Agreement) unconditional and irrevocable obligations of Borrower and accordingly shall not be conditional on performance by any Lender Party of any obligations save such as may be specified in this Agreement as required to be performed in order to give rise to a relevant obligation of Borrower thereunder.
Each of the obligations of the Guarantor under this deed is unconditional and irrevocable.
A Notice of Conversion shall constitute an irrevocable obligation of the Converting Partner to convert the applicable number of such Converting Partner ‘s Series HA Class B Units as of the Conversion Effective Date and the Converting Partner shall not be permitted to withdraw the Notice of Conversion , at any time, without the express prior written consent of the General Partner , which the General Partner may withhold in its discretion.
The Board intends the Plan to be permanent, but reserves the right at any time to modify, amend or terminate the Plan, provided, however, that benefits credited as provided herein shall constitute an irrevocable obligation of the Company.
I recommend that you never use the word irrevocable in connection with obligations, as it doesn’t make sense. You revoke something that benefits the other guy, not something imposed on you.
While I’m at it, I recommend that you not refer to obligations as unconditional or absolute, as it’s not clear enough what those terms mean.