Middle Primitive Elvish
palap
root. *beat
pal
root. beat
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 root appearing in both The Etymologies of the 1930s as well as the contemporaneous Tengwesta Qenderinwa (first version, TQ1) appearing as both short ᴹ√PAL “beat” and extended form ᴹ√PALAP of similar meaning (Ety/PALAP; PE18/33). In The Etymologies, the entry for short ᴹ√PAL was erased (EtyAC/PAL), and the extended root ᴹ√PALAP had a couple of derivatives: ᴹQ. palpa- “to beat, batter” and N. blab- “flap, beat (wings etc.)” (Ety/PALAP). A variant root ᴹ√PALAK may have been the basis for ᴹQ. palka- “to beat flat” from the Quenya Verbal System (QVS) of 1948 (PE22/114).
The short form ᴹ√PAL may also have been the basis for some words in the earlier Gnomish Lexicon of the 1910s: G. palta- “beat” [sic., rather than expected paltha-], G. paltha “blade (of swords, knives, oars, etc.); wide flat leaf; page of book” and G. plados “oar” (GL/63-64), though these words might be blended with root ᴱ√PALA “flatness” from the contemporaneous Qenya Lexicon (QL/71); see that entry for discussion.