
mehrjährig
multi-year
Extending over a period of several years or lasting several years.
Nach seiner mehrjährigen Weltreise kehrte er endlich nach Hause zurück.
After his multi-year trip around the world, he finally returned home.
multi-year / perennial
Loading your saved state.

multi-year
Extending over a period of several years or lasting several years.
Nach seiner mehrjährigen Weltreise kehrte er endlich nach Hause zurück.
After his multi-year trip around the world, he finally returned home.

perennial
In botany, denoting a plant that lives longer than two years and often blooms more than once.
Lavendel ist eine beliebte mehrjährige Pflanze für den Garten.
Lavender is a popular perennial plant for the garden.
The adjective is clearly built from 'mehr' (more/several) and 'jährig', a form of 'das Jahr' (the year). It literally means 'concerning several years' or 'lasting over several years'.
Für diesen Job ist mehrjährige Berufserfahrung erforderlich.
Several years of professional experience are required for this job.
In its general meaning, 'mehrjährig' (multi-year) is often used to describe the duration of experience, contracts, or training programs. Typical phrases are 'mehrjährige Erfahrung' (several years of experience), 'ein mehrjähriger Vertrag' (a multi-year contract), or 'eine mehrjährige Ausbildung' (a multi-year training program).
Sie hat einen mehrjährigen Mietvertrag für ihre Wohnung unterschrieben.
She signed a multi-year lease for her apartment.
You can recognize the botanical meaning from words related to gardens and plants. When the topic is 'Pflanzen' (plants), 'Stauden' (perennials), or 'Kräuter' (herbs), 'mehrjährig' (perennial) means that they do not die in winter and grow again the next year.
Rosen sind mehrjährige Pflanzen, die bei guter Pflege viele Jahre blühen.
Roses are perennial plants that bloom for many years with good care.
long-standing
Langjährig and mehrjährig both describe a duration measured in years. Langjährig emphasizes that a relationship or activity has already existed for many years. Mehrjährig merely says that something lasts several years, so it can also refer to a fixed future term.

Mit dem neuen Vertrag vereinbaren die Firmen eine mehrjährige Zusammenarbeit.
Under the new contract, the companies agree to a multi-year collaboration.
Nach zwölf gemeinsamen Jahren verlängern die Firmen ihre langjährige Zusammenarbeit.
After twelve years of working together, the companies are extending their long-standing collaboration.