hôm nay

hôm (“day”) +‎ nay (“this; now”).

• (Hà Nội) IPA^(key): [hom˧˧ naj˧˧]
• (Huế) IPA^(key): [hom˧˧ naj˧˧]
• (Saigon) IPA^(key): [hom˧˧ na(ː)j˧˧]
• (quick, colloquial speech) IPA^(key): [(m̩˧).naj˧˧]

hôm nay

1. today (on the current day)

   Synonym: bữa nay

• In fast and informal speech, hôm is often reduced to a barely audible syllabic nasal or completely ellipsed, so that only nay can be heard. Similar phenomenon can also be seen with hôm qua (“yesterday”).
• Note that although ngày is the normal word for "day" in Vietnamese, ngày nay means "nowadays", not "today".

• ngày nay (“these days, nowadays”)