Orchaldor's name is Sindarin and appears to mean "Eminent Man" (from the word orchal, 'superior', and the masculine suffix -dor).
Sindarin
orchaldor
masculine name. *Tall Lord
Elements
Word Gloss orchal “tall, tall; [N.] superior, eminent, lofty” -dor “*king, lord”
Orchaldor
Orchaldor
Husband of Ailinel (UT/210). His name seems to be a compound of orchal “tall” and -dor “lord”.
Conceptual Development: Some similar names appeared in The Etymologies from the 1930s: N. Orchelanath and (rejected) Orchallamath (EtyAC/KHAL², MBAT(H)).