1wheel 
/ˈwi:l/ noun
plural wheels /ˈwi:l/ noun 1 [count] a : one of the round parts underneath a car, wagon, etc., that rolls and allows something to move
▪ The car's rear wheels started to spin on the icy road. ▪ the wheels of a train/airplane ▪ a bicycle wheel ▪ a suitcase with wheels on the bottom — see also training wheels
b : a hard, round object that turns and causes machinery or a mechanical device to move — sometimes used figuratively ▪ You could almost see the wheels turning in his head. [=you could almost see him thinking about how to do something] — see also flywheel, paddle wheel, waterwheel 2 [count] : steering wheel
▪ She fell asleep at the wheel. [=she fell asleep while she was driving] ▪ He got behind the wheel [=he sat in the driver's seat] and sped off. ▪ I was nervous my first time behind the wheel. [=my first time driving a car] ▪ My sister offered to take the wheel. [=offered to drive] 3 [count] : something that is round like a wheel or that turns like a wheel
▪ a wheel of cheddar cheese — see also cartwheel, ferris wheel, pinwheel, potter's wheel, prayer wheel, spinning wheel 4 [count] a : an essential or functioning part of an organization, process, etc. — usually plural ▪ the wheels of government ▪ They hoped that the tax cuts would grease the wheels of the economy. [=would help the economy work better] ▪ With today's announcement, she has set the wheels in motion for a run for the presidency. [=she has begun to run for president]
b informal : an important person in an organization
▪ He's a big wheel [=bigwig] at the company. 5 wheels [plural] slang : car
▪ I couldn't get around easily without my wheels. ▪ She has a nice set of wheels. [=she has a nice car]
▪ The car's rear wheels started to spin on the icy road. ▪ the wheels of a train/airplane ▪ a bicycle wheel ▪ a suitcase with wheels on the bottom — see also training wheels
b : a hard, round object that turns and causes machinery or a mechanical device to move — sometimes used figuratively ▪ You could almost see the wheels turning in his head. [=you could almost see him thinking about how to do something] — see also flywheel, paddle wheel, waterwheel
▪ She fell asleep at the wheel. [=she fell asleep while she was driving] ▪ He got behind the wheel [=he sat in the driver's seat] and sped off. ▪ I was nervous my first time behind the wheel. [=my first time driving a car] ▪ My sister offered to take the wheel. [=offered to drive]
▪ a wheel of cheddar cheese — see also cartwheel, ferris wheel, pinwheel, potter's wheel, prayer wheel, spinning wheel
b informal : an important person in an organization
▪ He's a big wheel [=bigwig] at the company.
▪ I couldn't get around easily without my wheels. ▪ She has a nice set of wheels. [=she has a nice car]
a/the squeaky wheel gets the grease/oil
— used to say that someone who complains or causes problems is more likely to receive attention or help than someone who stays quiet and does not cause problems
reinvent the wheel — see reinvent
spin your wheels — see 1spin
wheels come/fall off
informal ◊If the wheels come/fall off, someone or something fails in a sudden or unexpected way.
▪ The pitcher was doing well for the first four innings, then the wheels fell off in the fifth.
▪ The pitcher was doing well for the first four innings, then the wheels fell off in the fifth.
wheels within wheels
: a situation that is complex and difficult to deal with because it involves many different things
▪ The problem seems simple at first, but there are wheels within wheels.
▪ The problem seems simple at first, but there are wheels within wheels.
