介系个老词儿啦，字典上说你想的那意思是第四种词义，嘿嘿～

Main Entry: 1gay
Pronunciation: \712;gā\
Function: adjective
Etymology: Middle English, from Anglo-French gai, of Germanic origin; akin to Old High German gāhi quick, sudden
Date: 14th century
1 a: happily excited : merry b: keenly alive and exuberant : having or inducing high spirits
2 a: bright , lively b: brilliant in color
3: given to social pleasures ; also : licentious
4 a: homosexual b: of, relating to, or used by homosexuals

synonyms：lively