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.
thon
root. *pine
mālō
noun. friend
yel
root. friend
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.
The unglossed root ᴹ√THON appeared in The Etymologies of the 1930s with derivatives Ilk. thōn and N. thaun “pine-tree” (Ety/THOL); according to Hostetter and Wynne, Christopher Tolkien incorrectly recorded this root as ᴹ√THŌN, but that was actually just the Ilkorin form of the word. Tolkien explained the somewhat unusual Noldorin form N. thaun as the result of a loan for Ilk thōn, with the Noldorin word being adapted as ō [ǭ] < [primitive] ā; this loan must have occurred in the period after [[on|ancient long [ō] became [ū]]] in Old Noldorin, but before [[n|[ǭ] (from [ā]) became [au]]]. This 1930s root was used mainly to explain the name Ilk. Dorthonion “Land of Pines”.
In a 1955 letter to David Masson, Tolkien derived S. thôn “pine” from ✶stŏna (PE17/82). However, in Words, Phrases and Passages from the Lord of the Rings written in the late 1950s or early 1960s Tolkien derived this element of S. Dorthonion from {stāna >> thānĭ >>} thŏno, apparently coming full circle back to the 1930s root √THON (PE17/81).