Gnomish
gân
adjective. young
gwiog
adjective. young
gwion
adjective. young
gwiw
adjective. young
gân ar gantha
*young and old, (lit.) young and adult
There are more words but they are from Tolkien's earlier conceptional periods. Tolkien likely changed these words as he evolved the aesthetics and completeness of the languages. You may even find languages that Tolkien later rejected. Do not mix words from different time periods unless you are familiar with the phonetic developments.
gân
adjective. young
gwiog
adjective. young
gwion
adjective. young
gwiw
adjective. young
gân ar gantha
*young and old, (lit.) young and adult
Below: Tolkien's Late Period (1950–1973). These are from Tolkien's late conceptual period — his most settled forms of the languages. Prefer these over the earlier ones above when composing new text.