Idioms:

Good-for-nothing
Meaning: to be worthless
Good grief!
Meaning: used to show surprise (good or bad)
Good old days
Meaning: earlier times which everyone remembers as being better than the present
Good riddance
Meaning: used to express happiness when you lose or break something that you do not like or want, used when someone who you don't like leaves
Good riddance to bad rubbish
Meaning: used to show that you are happy that someone or something has been taken or sent away
Good samaritan
Meaning: someone who helps others when they are in need, with no discussion for compensation, and no thought of a reward
Good sport
Meaning: a person who loses a competition or game without complaining
Goof off
Meaning: to waste time, to fool around, to not work or be serious
Goof up
Meaning: to make a mistake, to perform badly
Goose is cooked
Meaning: one has been discovered to have done something wrong and is now in trouble, one is finished, one's chances are ruined
Gospel truth
Meaning: the undeniable truth
Got a thing going
Meaning: engaged in an activity with someone (in romance or business)
Grab a bite
Meaning: to get something to eat
Grace with one's presence
Meaning: to honor someone or something by being present
Grain of truth
Meaning: the smallest amount of truth
Grasp at straws
Meaning: to try something with little hope of success
Grass is always greener on the other side
Meaning: a place or situation that is far away or different seems better than one's present situation
Grate on nerves
Meaning: to annoy or bother someone
Graveyard shift
Meaning: working hours from about 12:00 am to 8:00 am The time of the day when most other people are sleeping
Gravy train
Meaning: a job that gives one much money compared with what you do
Gray area
Meaning: something difficult to define or put into a particular category, something that is not clear
Grease palm
Meaning: to pay money to someone for some special favor
Greasy spoon
Meaning: a small and cheap eating place with basic but not great food
Great minds think alike
Meaning: intelligent people think like each other
Greatest thing since sliced bread
Meaning: the best thing that there ever was
Green
Meaning: to be inexperienced or immature
Green room
Meaning: the waiting room, especially for those who are about to go on a tv or radio show
Green with envy
Meaning: to be very jealous, to be full of envy
Grin and bear it
Meaning: to endure something unpleasant with good humor
Grind to a halt
Meaning: to slow down and stop (like a machine when it is turned off)
Grist for the mill
Meaning: something that can be used for one's advantage
Grit one's teeth
Meaning: to grind one's teeth together in anger or determination or reluctance
Gross out
Meaning: to make someone sick or disgusted
Ground floor
Meaning: the first or best chance (especially in a business)
Ground
Meaning: to take away someone's privileges (usually used for teenagers)
Grounds for
Meaning: the basis or reason for legal action or a complaint
Grow on
Meaning: to become acceptable to someone or liked by someone
Grow out of
Meaning: to abandon something as one matures or becomes older
Grow to do/like
Meaning: to gradually begin to do something or like someone or something
Grunt work
Meaning: hard and thankless work
Guard against
Meaning: to take care to avoid someone or something
Guest of honor
Meaning: the special person for whom a party or ceremony is held
Gulp for air
Meaning: to desperately try to get some air or a breath
Gum up
Meaning: to cause something not to work, to make something go wrong
Gun for
Meaning: to look hard for a chance to harm or defeat someone
Gung-ho
Meaning: to be enthusiastic, to be full of eagerness
Gut feeling/reaction
Meaning: a personal or intuitive feeling or response
Gyp out of
Meaning: to cheat someone
English Idioms from (Good - Gyp)
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