What's the adjective for heightless? Here's the word you're looking for.
Included below are past participle and present participle forms for the
verbs heighten, high and highen which may be used as adjectives within certain contexts.
(of a card or hand) Winning; able to take a trick, win a round, etc.
(of meat, especially venison) Strong-scented; slightly tainted/spoiled; beginning to decompose.
(slang) Intoxicated; under the influence of a mood-altering drug, formerly (until the early 20th century) usually alcohol, but now (by the mid 20th century) usually not alcohol but rather marijuana, cocaine, heroin, etc.
(nautical, of a sailing ship) Near, in its direction of travel, to the (direction of the) wind.