Hi, my Prof just used it in a tweet, I noticed the irregularity of spelling:
First the last comment is "de-condo", not di.
I also don't think regardless and irregardless are the same (from another thread).
'Di umano' is similar to 'di mapasubalian', undeniably.
'Umano' is similar 'mapasubalian', or deniably.
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My guess is that 'ir' in irregardless is air or show-off with anger as in 'ire'.
I avoided googling, I like my reasoning fresh from a new perspective. The word 'umano' hints on curious suspicion than definite likelihood, giving 'di umano' the quality of heresay. It is an overused attention spinner in local broadcasting, to be misspelled.
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The translation to 'undeniably' with a quality of a heresay is in the negation of 'deny' and its adverb from which implies an action becoming, in comparison with 'undeniable', the adjective form, which is a state of being but still in negative invocation.
The word 'di mapasubalian' is not used in colloquial conversations or news reporting. However, I deemed it closer to 'di umano' because the root word 'bali' which means 'bend' is near to 'umano' which now colloquially means 'give in'. (As in 'ano', a filler for unexpressed, adulterated Filipino.)
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break, bend, twist
Bali Meaning | Tagalog Dictionary