Modern Vietnamese contains a number of lemmas and forms derived from historically affixed forms.
This article excludes the animate prefix *ʔa- since it did not produce new words.
Proto-Vietic infix *-rn- derived nouns from verbs. As some verbs in Vietnamese also became nouns through semantic extension, the meaning of the infixed words and the uninfixed nouns sometimes became synonymous.
| Affixed form | Unaffixed form | Note | |
|---|---|---|---|
| 1. | nan (“bamboo slat, bamboo tape”) | đan (“to weave”) | |
| 2. | nẹp (“clip, nipper”) | kẹp (“to pinch, to clamp”) | |
| 3. | nút (“bung, cork”) | đút (“to plug, to insert”) | |
| 4. | nải (“hand of banana”) | chải (“to comb”) | Compare the relationship between Khmu criəs ("to comb") and cntriəs ("clf. for a hand of bananas"), Khmer សិត (sət) and ស្និត (snət). |
| 5. | nếp (“fold”) | xếp (“to fold”) | |
| 6. | nệm (“mattress”) | đệm (“to back, to put under”) | |
| 7. | nọc (“venom, stinger; stake”) | chọc (“to prick, to poke”) | The infixed form now mainly means "venom". |
| 8. | niền (“rim”) | viền (“to hem, to edge”) | |
| 9. | nĩa (“fork”) | xỉa (“to pick, to jab”) | |
| 10. | nạo (“curette, scraper”) | cạo (“to scrape”) | The infixed form is now mostly used as verb. |
| 11. | nước (“move, step”) | bước (“to step”) | |
| 12. | nuộc (“turn of bamboo tape”) | buộc (“to bind, to tie”) | |
| 13. | nâng (“to raise, to lift”) | dâng (“to rise, to offer”) | The infixed form is now used as verb. |
| 14. | nêu (“bamboo pole”) | bêu (“to raise, to expose”) | |
| 15. | nụ (“flower bud”) | bú (“to suckle”) | The infixed form probably originally meant "nipple", cf. Maleng Bro prnuːʔ ("breast"). |
| 16. | nét (“line”) | quét (“to sweep, to paint, to coat”) quẹt (“to rub, to wipe”) |
|
| 17. | níu (“to pull back”) | víu, bíu (“to cling to”) | The infixed form is now used as verb. |
| 18. | nêm (“wedge”) | chêm (“to wedge”) | |
| 19. | nịt (“belt”) | rịt (“to fasten; to tie”) or thít (“to fasten”) |
|
| 20. | nơm (“a fishing tool”) | đơm (“to catch fish with nơm”) | |
| 21. | nau (“birth pang, belly pain”) | đau (“to be painful, to be hurt”) | |
| 22. | nạy (“to pry, to prize”) | cạy (“to pry, to prize”) | The infixed form is now used as verb. |
| 23. | nứng (“horny, aroused”) | cứng (“to be hard”) | |
| 24. | nắp (“lid”) | đắp (“to cover”) | |
| 25. | nuốc (“broom”) | xuốc (“to sweep”) | Both words are only found in certain North Central dialects. Cf. Santali ᱡᱚᱜ (jôk’, “to sweep”) and ᱡᱚᱱᱚᱜ (jônôk’, “broom”). |
| 26. | neo (“anchor”) | xeo (“to row”) | xeo is archaic, glossed as remo de iangada in the Dictionarium Annamiticum Lusitanum et Latinum. |
| 27. | nạng (“crutches”) | chạng, giạng (“to spread out, to split diagonally”) | |
| 28. | nợ (“debt”) | bợ (“to borrow”) |
These cases are fewer and it is harder to pinpoint their history.
| Affixed form | Unaffixed form | Note | |
|---|---|---|---|
| 1. | non (“young, tender”) | con (“child”) | |
| 2. | nết (“custom, manner, conduct”) | vệt (“streak, long trace”) vết (“stain, spot”) |
|
| 3. | nấc (“rung, grade, notch”) | bậc (“rung, stair, step”) |
Proto-Vietic prefix *pr- ~ *p- derived verbs from verbs.
| Affixed form | Unaffixed form | Note | |
|---|---|---|---|
| 1. | mướn (“to rent, to hire”) | mượn (“to borrow”) | |
| 2. | dựng (“to set up, to erect”) | đứng (“to stand”) | |
| 3. | tràn (“to overflow”) | lan (“to spread”) | |
| 4. | giết (“to kill”) | chết (“to die”) | cf. Phong pceːt⁷ "to kill" (< *k-pr-ceːt) was probably independently formed. |
| 5. | giuống (“to put down”) | xuống (“to go down”) | giuống is obsolete in the mainstream dialects. |
| Affixed form | Unaffixed form | Presumed affix | |
|---|---|---|---|
| 1. | trên (“on, above”) | lên (“to go up”) | *k- |
| 2. | làm (“to do, to make”) | là (“to be”) | *-m |
| 3. | trộn (“to stir, to blend”) | lộn (“to mix up”) | *g- |
| 4. | quê (“hometown (< village)”) | về (“to return”) | *k- |
| 5. | mọi (“barbarian, savage (originally human being < dibbler)”) |
mói (“to dig out, to dibble”) | Unknown |
| 6. | nay (“now”) | này (“this”) | Unknown |
| 7. | mặt (“face”) | mắt (“eye”) | Unknown |
| 8. | mốt (“the day after tomorrow”) | một (“one”) | Unknown |
| 9. | miếng (“piece, mouthful”) | miệng (“mouth”) | Unknown |
| 10. | dấy (“to raise”) | dậy (“to wake up, to rise”) | Unknown |
| 11. | tròng (“to insert, to put in”) | trong (“inside”) | Unknown. The causative prefix might be possible, but phonetically and semantically (the root is not a verb), it is not straightforward. |