Throughout the world, Illtyd (Illtyd 
) is a very rare male given name. The given name Illtyd is characteristic of Northern Europe, particularly the United Kingdom, where it is a very rare masculine name.
| VARIANT | COUNTRY |
|---|---|
| Illtyd | Canada, United States, Philippines, United Kingdom |
|
illtyd trethowan British priest (1907-1993), GB (b. 1907) |
|
| illtyd williams (b. 1856) |
|
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| illtyd buller pole-evans South African botanist and mycologist (1879-1968), GB (b. 1879) |
|
|
| illtyd edward mostyn (1881-1958) (b. 1881) |
|
|
| illtyd humphry mostyn (1907-1982) (b. 1907) |
|
|
| illtyd david (b. 1906) |
|
|
|
illtyd nicholl vicar, GB |
|
| illtyd harrington Welsh politician, GB (b. 1931) |
|
|
| illtyd williams rugby league player |
|