A word appearing as G. och “egg” in the Gnomish Lexicon of the 1910s (GL/62), likely based on the early root ᴱ√OHO from which Qenya “egg” words were derived (QL/69). It has a somewhat unusual plural form uith, likely from primitive ✱oχ-þ- as suggested by Roman Rausch with the vocalization of oχ to oi which then became ui (HPG/§2.8).
Neo-Sindarin: I’d retain ᴺS. och “egg” for purposes of Neo-Sindarin based on a Neo-Root ᴺ√OKH, but I’d give it a more normal Sindarin plural: ych “eggs”.
A verb appearing as G. uitha- “lay eggs, nest” in the Gnomish Lexicon of the 1910s (GL/74), likely derived from the early root ᴱ√OHO [OΧO] which was the basis for ᴱQ. ohte “egg” in the contemporaneous Qenya Lexicon (QL/69). This verb probably represents the vocalization of ancient χ to i before th [θ], after which the resulting oi became ui; compare G. fuitha- “hide” < ᴱ√foχo (GL/36).
Neo-Sindarin: I would adapt this verb as ᴺS. oetha- for purposes of Neo-Sindarin, based on the Neo-Root ᴺ√OKH “egg”, since a similar vocalization of χ occurred in Sindarin, but the resulting oi became oe.