Gnomish
blant
adjective. flat, open, expansive; candid, blunt (of words)
Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!
An adjective in the Gnomish Lexicon of the 1910s appearing as G. blant with the glosses “flat, open, expansive; candid, blunt (of words)” (GL/19), apparently based on (a variant of?) the early root ᴱ√PALA having to do with flat things (QL/71).
Neo-Sindarin: Since √PAL continued to be used for wide and flat things in Tolkien’s later writing, I would retain but adapt this word as ᴺS. plant “flat, open, expansive; candid, blunt (of words)” for purposes of Neo-Sindarin.