Princeton's WordNet

1. meadowlark, lark(noun)

   North American songbirds having a yellow breast

   Synonyms:
   lark, meadowlark, pipit, titlark, escapade

2. pipit, titlark, lark(noun)

   a songbird that lives mainly on the ground in open country; has streaky brown plumage

   Synonyms:
   lark, meadowlark, pipit, titlark, escapade

3. lark(noun)

   any of numerous predominantly Old World birds noted for their singing

   Synonyms:
   meadowlark, pipit, titlark, escapade

4. escapade, lark(verb)

   any carefree episode

   Synonyms:
   risky venture, adventure, dangerous undertaking, titlark, pipit, meadowlark, lark, escapade

5. frolic, lark, rollick, skylark, disport, sport, cavort, gambol, frisk, romp, run around, lark about(verb)

   play boisterously

   Synonyms:
   boast, sport, lark, frolic, romp, run around, amuse, lark about, divert, rollick, disport, cavort, frisk, gambol, feature, skylark