What is the meaning of the word "at the least"?

Definitions:

not less than adverb
- At the least, he should call and apologize for missing the meeting.
not less than adverb
- At the least, he should call and apologize for missing the meeting.
not less than adverb
- He has to admit his mistakes and at the least try to make things right.
not less than adverb
- I don't expect him to come to my party, but at the least, he could RSVP.
not less than adverb
- At the least, he should make an effort to understand my feelings.
not less than adverb
- At the least, she should have told me the truth instead of lying to me.
not less than adverb
- At the least, she could have shown some empathy towards my situation.
not less than adverb
- At the least, they should have given me a warning before firing me.
not less than adverb
- At the least, he should have acknowledged my presence instead of ignoring me.
not less than adverb
- At the least, they could have shown some gratitude for my hard work.
not less than adverb
- At the least, she should have given me a chance to explain myself.
not less than adverb
- At the least, he could have shown some remorse for his actions.
not less than adverb
- At the least, they should have considered my perspective before making a decision.
not less than adverb
- At the least, she could have treated me with respect instead of belittling me.