the highest, strongest, or best point, value, or level of skill:
Prices reach a peak during August.
Beat the egg whites until they are stiff enough to form firm peaks.
We saw a victory by an athlete at the very peak of her fitness and career.
the pointed top of a mountain, or the mountain itself:
It is one of the most difficult peaks to climb.
the flat curved part of a cap that goes above the eyes of the person who is wearing it
Peak times are the times when most people are using or doing something:
Traffic congestion is really bad at peak periods (= when it is busiest).
It is most expensive to advertise at peak viewing times (= those with the most people watching).
Don't go there in the peak (= busiest) season - it'll be hot and crowded.
Peak levels or rates are when they are at their highest:
peak rate electricity
used to describe something that has become so popular and common that it is no longer fashionable or people start to dislike it:
I think we've reached peak beard (= beards were fashionable, but now too many people have them).
to reach the highest, strongest, or best point, value, or level of skill:
Official figures show that unemployment peaked in November.
to reach the highest point, value, or level:
Official figures show unemployment peaked in November.
the pointed top of a mountain, or the mountain itself
a period during which something reaches its highest level, price, rate, etc.:
At its peak, the company was valued at £1.5 billion.
Several internet service providers tested in the evening peak failed to deliver the new target for high-speed internet.
be above/below the peak of sth The shares have started to recover but are still far below their 12-month peak.
hit/reach/rise to a peak Investors were looking beyond the UK market because they feared it might have reached a peak.
all-time/record/highest peak
Markets are subject to strong peaks and troughs due to economic cycles.
relating to the highest level, price, rate, etc. that something reaches:
The comparison site provides information on peak and off-peak rates across all the major mobile networks.
Service providers keep spare capacity to meet peak demand.
peak efficiency/performance
relating to a period of time during which more people are using a service or system than during any other period:
The new facility could increase the number of packages shipped to 30,000 from 10,000 during the peak holiday season.
peak hours/periods/times The Underground often operates a crowd-control system at peak periods.
(also peak out)
to reach the highest level, price, rate, etc.:
Official figures show that unemployment peaked in November.
peak (out) at sth There was growing belief in the City that base rates may have peaked at 4.75%.
Despite talk of the market peaking out, investors are still buying rather than selling.