Without paying attention to the present situation; despite the prevailing circumstances. In spite of everything; anyway.
From 'regard' (from Old French 'regarder' meaning 'to look at') plus the suffix '-less' meaning 'without.' The word literally means 'without looking' or 'without consideration' of circumstances.
The word 'regardless' literally means 'without looking' - it's about proceeding without regard to what you might see around you. The controversial 'irregardless' is actually a double negative (ir- + regard + -less) that some argue makes logical sense as an intensive form.
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