The form rhaes in the Etymologies is a misreading according to VT/46:10
Noldorin
both
noun. puddle, small pool
both
noun. puddle, small pool
rhas
noun. horn [of both animals and mountains]
ath-
prefix. on both sides, across
ath-
prefix. on both sides, across
ui-
prefix. twi-
cam
noun. hand
cam
noun. hand
camb
noun. hand
camm
noun. hand
camm
noun. hand
iath
preposition. across
lhîn
noun. pool
lhîn
noun. pool
liniath
noun. pools
mō
noun. hand
parf
noun. book
parf
noun. book
rhas
noun. horn (especially on living animal, but also applied to mountains)
rhasg
noun. horn (especially on living animal, but also applied to mountains)
rhasg
noun. horn
rhim
noun. cold pool or lake (in mountains)
rhimb
noun. cold pool or lake (in mountains)
rhom
noun. horn, trumpet
tad
cardinal. two
tarag
noun. horn
tarag
noun. steep mountain peak
thar-
prefix. across, athwart, over, beyond
tild
noun. horn, point
till
noun. horn, point
till
noun. horn
tâd
cardinal. two
tâd
cardinal. two
ON. hand