Qenya
kas
noun. head
kas
adverb. upwards, towards the top
kas
noun. head
kas
noun. case, vessel
kapsa
noun. case, vessel, case, vessel, *container
kár
noun. head
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.
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.
A word in the Declension of Nouns (DN) from the early 1930s glossed “case, vessel” (PE21/20). It appeared in both a short form kas (kaps-) and longer kapsa (PE21/27). It might be derived from ᴹ√KAB “hollow” as suggested by Raccoon in a Discord chat from 2022. If so, its general meaning might be “✱container”.