A word appearing as G. {nort >>} nost in the Gnomish Lexicon of the 1910s with three distinct meanings: “birth”, “blood = high birth” and “birthday”, though the last sense also applied to the word G. {noss >>} nôs (GL/61). It is clearly based on the early root ᴱ√NŌ “become, be born” (QL/66). G. nosteg seems to be an adjectival variant in the phrase dana nosteg “birthday = ✱day of birth” (GL/61)
Neo-Sindarin: The usual Neo-Sindarin word for “birth” is ᴺS. onnad, gerund of the verb onna- “✱to give birth”; I’m not sure who coined this neologism, but it has been in use for some time.
A word for “bird” in the Gnomish Lexicon of the 1910s appearing next to G. bilinc “sparrow”, but this word was deleted and the gloss for bilinc was expanded to “a small bird, especially sparrow” (GL/22-23). The form bil appeared in a couple other places in the Gnomish Lexicon (GL/23, 31), but seems to represent a “root” rather than a word. Tolkien indicated bil was derived from ᴱ✶du̯il (GL/31), but the exact mechanism whereby du̯- became b- isn’t clear, but a similar change is seen in 1920s ᴱ✶du̯ag- > ᴱT. baga- “beat” and ᴱ✶tu̯ak- > ᴱQ. pak- “apply, attach” (PE14/66).