different between guestless vs gustless

English

guest +? -less

guestless (not comparable)

Without a guest.
- 1954, Charles A. Smythwick, False measure
  Nobody was dancing and no one was at the piano. The radio was on. The bartender was leaning across a guestless bar.

From Latin gustus (“a tasting”), and suffix -less.

gustless (comparative more gustless, superlative most gustless)

(obsolete) tasteless; insipid
- 1683, Sir Thomas Browne, Observations Upon Several Plants Mentioned In Scripture
  […] they might after give the expressed and less useful part of the cods and remaining pulp unto their swine: which, being no gustless or unsatisfying offal, might be well desired by the prodigal in his hunger.

gust +? -less

gustless (comparative more gustless, superlative most gustless)

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