Learner's definition of HAY
[noncount]
1
: grass that has been cut and dried to be used as food for animals(用作饲料的)干草 2
US, informal : a small amount of money少量的钱 —
usually used in negative statements通常用于否定句
a roll in the hay
— see 3roll
make hay (while the sun shines)
: to get value or use from an opportunity while it exists : to not waste an opportunity晒草要趁阳光好;抓紧时机;趁热打铁