
English word less-than-stellar comes from English stellar, English less
stellar (English)
(astronomy, notcomp) Of, pertaining to, or characteristic of stars.. Exceptional; wonderful.. Heavenly.
less (English)
(obsolete) unless In lower degree.. To a smaller extent. (now, _, archaic, _, except with numbers) ; smaller. [from 11th c.]. (proscribed) A smaller number of; fewer. [from 9th c.]. A smaller amount (of); not as much. [from 14th c.] Minus; not including (obsolete) To make less; to lessen.
less-than-stellar (English)
(slang, sarcastic) Mediocre; not satisfactory; not very good, poor; not meeting standards or expectations.