"ethreal" is probably misspelled. Trying ethereal instead Definition of ethereal
ethereal has definitions from the fields of religion,chemistry
1
[ adjective ] characterized by lightness and insubstantiality; as impalpable or intangible as air

Examples

"figures light and aeriform come unlooked for and melt away"- Thomas Carlyle "aerial fancies" "an airy apparition" "physical rather than ethereal forms"

2
[ adjective ] (chemistry) of or containing or dissolved in ether

Examples

"ethereal solution"

3
[ adjective ] (religion) of heaven or the spirit

Synonyms

celestial supernal

Examples

"celestial peace" "ethereal melodies" "the supernal happiness of a quiet death"

4
[ adjective ] characterized by unusual lightness and delicacy

Synonyms

gossamer

Examples

"this smallest and most ethereal of birds" "gossamer shading through his playing"

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