guideline (n.)youdaoicibaDictYouDict
1785, "line marked on a surface before cutting," from guide + line (n.). Meaning "rope for steering a hot-air balloon" is from 1846. In figurative use by 1948. Related: Guidelines.
stew (v.)youdaoicibaDictYouDict
late 14c., transitive "to bathe (a person or a body part) in a steam bath," from Old French estuver "have a hot bath, plunge into a bath; stew" (Modern French étuver), of uncertain origin. Common Romanic (cognates: Spanish estufar, Italian stufare), possibly from Vulgar Latin *extufare "evaporate," from ex- "out" + *tufus "vapor, steam," from Greek typhos "smoke." Compare Old English stuf-bæþ "hot-air bath;" see stove.

Intransitive use from 1590s. Meaning "to boil slowly, to cook meat by simmering it in liquid" is attested from early 15c. The meaning "to be left to the consequences of one's actions" is from 1650s, especially in figurative expression to stew in one's own juices. Related: Stewed; stewing. Slang stewed "drunk" first attested 1737.
aerostatyoudaoicibaDictYouDict
"An airship or hot-air balloon", Late 18th century: from French aérostat, from Greek aēr 'air' + statos 'standing'.
aeronautyoudaoicibaDictYouDict
"A traveller in a hot-air balloon, airship, or other flying craft", Late 18th century: from French aéronaute, from Greek aēr 'air' + nautēs 'sailor'. More see asterisk, nausea