oar, ski pole, chef, lean

• oar [countable]
• 1 a long pole with a wide flat blade at one end, used for rowing a boat [↪ paddle]
• 2

   put/stick/get your oar in

  British Englishinformal to get involved in a conversation or situation when the other people do not want you to:
• We were getting along fine until you stuck your oar in.

• ski pole [countable]
• one of two pointed short poles that you hold to help you balance and push off the snow when skiing

• chef [countable]
• a skilled cook, especially the main cook in a hotel or restaurant:
• a master chef
• a pastry chef
• WORD FOCUS: restaurant 
• the person who serves you in a restaurant: waiter, waitress, serverAmerican English, waitperson American English
• the person who cooks your food: chef
• the person who welcomes the guests: maitre d', host/hostessAmerican English
• a list of the food: menu also bill of fare formal
• a list of wines and alcoholic drinks: wine list also drink list American English
• a piece of paper that shows the amount you have to pay for your meal: bill British English/check American English
• extra money you leave for the waiter or waitress: tip/gratuity formal
• money that the restaurant charges for service: service charge, cover charge, corkage
• restaurant
• 
  
• 
  
• ➔ See also restaurant

lean past tense and past participle leaned or leant especially British English

1 [intransitive always + adverb/preposition] to move or bend your body in a particular direction

lean forward/back/over etc

They were leaning forward, facing each other.

Lean back and enjoy the ride.

She leant towards him and listened.

2 [intransitive always + adverb/preposition] to support yourself in a sloping position against a wall or other surface

lean against/on

He was leaning on the bridge, watching the boats go by.

3 [intransitive,transitive always + adverb/preposition]to put something in a sloping position where it is supported, or to be in that position

lean (something) against/on something

A huge mirror was leaning against the wall.

He leant his bicycle against the fence.

4 [intransitive] to slope or bend from an upright position:

trees leaning in the wind

lean on somebody 

phrasal verb

1 to depend on someone for support and encouragement, especially at a difficult time:

The couple lean on each other for support.

2 informal to try to influence someone, especially by threatening them:

He won't pay unless you lean on him.

lean towards something 

phrasal verb

to tend to support, or begin to support, a particular set of opinions, beliefs etc:

Canada, the UK and Japan leant towards the US view.

Definition from the Longman Dictionary of Contemporary English
Advanced Learner's Dictionary.