reserve · verb I or T /rɪˈzɜrv/Full view
reserve (ARRANGE TO HAVE)
B1 to arrange to have a seat on an aircraft, a room in a hotel, etc.
Dictionary examples:

I’m sorry, this seat is reserved.

It’s a popular restaurant, and you’ll have to reserve well in advance.

I reserved a room at the Lamb Hotel.

Learner example:

You can reserve the tickets. (Preliminary English Test; B1; Farsi)

reserve (KEEP)
B1 often passive to not allow people to use something because it is only for a particular person or for a particular purpose
Dictionary examples:

This space is reserved for ambulances only.

These seats are reserved for the elderly and the disabled.

He reserved the right to veto any future plans.

Learner example:

You can also use streets reserved for walker[s]. (First Certificate in English; B2; French)

reserve · noun /rɪˈzɜrv/
reserve
C2 C a supply of something that you keep until it is needed
Dictionary examples:

emergency cash reserves

I have a reserve of canned food in case of emergency.

Learner example:

The dependence on oil is a menace because oil reserves will disappear and because at this time we have no other invention to replace it. (Certificate of Proficiency in English; C2; French)

in reserve
C1 ready to be used if or when you need it
Dictionary example:

She keeps a little money in reserve.

Learner example:

It would be an idea to have some activity in reserve if you have to cancel something, such as the boat trip on the Thames. (Certificate in Advanced English; C1; Swedish)

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