echoless

Etymology tree
Proto-Indo-European *sweh₂gʰ-der.
Proto-Hellenic *wākʰā́
Ancient Greek ἠχή (ēkhḗ)
Proto-Indo-European *-ṓy
Ancient Greek -ώ (-ṓ)
Ancient Greek ἠχώ (ēkhṓ)bor.
Latin ēchō
Medieval Latin ēccōbor.
Middle English eccho
English echo
Proto-Indo-European *lewh₁-
Proto-Indo-European *lewHs-der.
Proto-Germanic *leusaną
Proto-Germanic *lausaz
Proto-Germanic *-lausaz
Proto-West Germanic *-laus
Old English -lēas
Middle English -les
English -less
English echoless
From echo + -less.