| Word element | Meaning | Example of use (sound file links underlined) |
|---|---|---|
| sain, san, sant,saint | saint | Llantrisant |
| sarn, (plural sarnau) | causeway | Bwlch-y-sarnau |
| sych | dry | Sychnant |
T - (TH can be a mutation of T)
| Word element | Meaning | Example of use (sound file links underlined) |
|---|---|---|
| tafarn, (plural tafarnau) | tavern | Tafarn-y-garreg |
| tair | see tri | |
| tal | end | Tal-y-bont |
| tan | end, below | |
| tarren, (plural tarenni) | rocky height, precipice | |
| teg | fair, beautiful | Pant-teg |
| tir | land, territory | Tirymynach |
| tomen | mound | |
| ton | grassland, lea | Tonypandy |
| traeth | strand, beach, shore | |
| trallwng | wet bottom land | |
| traws | cross, transverse; direction, district | Trawsfynydd |
| tre(f) | homestead, hamlet, town | Tredegar |
| tri, (feminine tair) | three | Llantrisant |
| troed | foot | Troed-y-rhiw |
| tros | over | Trostre |
| trum | ridge | |
| trwyn | point, cape (literally nose) | |
| twyn | hillock, knoll | Twynllannan |
| ty, (plural tai) | house | Ty-croes; Tai-bach |
| tyddyn, ty'n | small farm, holding |
| Word element | Meaning | Example of use (sound file links underlined) |
|---|---|---|
| uchaf | upper, higher, highest | Cwmtwrch Uchaf |
| uchel | high | |
| uwch | above, over |
| Word element | Meaning | Example of use (sound file links underlined) |
|---|---|---|
| y, yr, 'r | (definite article) the | Tanygrisiau; Tonyrefail; Godre'r-graig |
| ych | ox | |
| yn | in | |
| ynys | island, holm, water meadow | Ynysybwl |
| ysbyty | hospital, hospice | Ysbyty Ifan |
| ystrad | valley floor, strath | Ystradyfodwg |
| ystum | bend (in river) | Llanystumdwy |