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.
lenwi
noun. length, distance
lenu-
verb. to stretch, extend in length, trail; ?to approach
A deleted verb from the Gnomish Lexicon of the 1910s glossed “to stretch, extend in length, trail” (GL/53), the equivalent of ᴱQ. lenu- “stretch” under the early root ᴱ√LENE “long” from the contemporaneous Quenya Lexicon (QL/53). In the Gnomish Lexicon, Tolkien also had G. lenu- as a possible equivalent to G. lentha- “approach”, but this second instance of lenu- was marked with a “?” (GL/53).
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 rejected word for “length, distance” in the Gnomish Lexicon of the 1910s based on G. len “long” (GL/53).
Neo-Sindarin: For purposes of Neo-Sindarin, I would use ᴺS. annas for “length” based on later S. and “long”, but for “distance” I would use attested S. haered.