⋄ Tar >> Aran >> Galdaran (TI:261,262)
⋄ Galathir = Galað-hîr ’tree-lord’ (TI:249)
⋄ Arafain (TI:256)
These are earlier names of Celeborn.
The first two forms must simply mean ’king’ – the former is most probably from the mentioned TAR- (VT45:17) or TĀ-, TAƷ- ’high, lofty, noble’ (compare also Tarkilmar), the latter is given under ƷAR-; thus the Lords of Lothlórien are Aran and Rhien ’King’ and ’Queen’.
Galdaran contains #gald-, obviously a contraction of GÁLAD- + aran ’king’, thus meaning *’tree-king’. Hence, the Lords are now Galdaran and Galdrien *’Tree-king’ and *’Tree-queen’. Although d becomes lenited in Noldorin after a vowel, as in galadh ’tree’, the medial combination -ld- is apparently allowed – cf. Galdor, later Gallor (GALA-, GÁLAD-).
Galathir is again self-explanatory with the indicated etymology, formed with galadh ’tree’ (GÁLAD-) and hîr ’master’ (KHER-).
And finally the last form should probably mean *’white king’ with the element ara- ’high, noble, royal’ (Silm.index), also S. ara *’king’, ar/ara/aran ’prefixes of excellence especially in royal names’ (PE17:147) and fain *’white’ (The Etymologies give just fein ’white’ under SPAN-, but compare for instance the variation in N. lhein, lhain ’free(d)’ (LEK-)).