Tireless

adj.resilient, energeticwarm

What it means

Sustaining energetic effort for an unusually long time.

Reach for it when honoring prolonged work or advocacy that seems not to lose force

The tireless coordinator found a host family for every displaced student.

everyday
energetic
when liveliness is visible but long duration is unproved
not when Energetic says nothing about persistence across months or setbacks.
everyday
hardworking
when dependable effort matters without claiming boundless energy
not when Hardworking is broader and less emphatic about duration.
warm
steadfast
when loyal constancy is more important than pace
not when Steadfast can be quiet and still, unlike the active exertion implied by tireless.
professional
dedicated
when commitment explains the sustained effort
not when Dedicated may remain true even when a person sensibly rests or reduces their hours.
professional
relentless
when pressure and forward drive never let up
not when Relentless can sound harsh, exhausting, or hostile when warmth is intended.
formal
untiring
when steady energy is meant literally and without flourish
not when Untiring can sound dated and does not highlight devotion to a cause.
literary
indefatigable
when elevated praise for seemingly endless energy is appropriate
not when Indefatigable is too ornate for a plain resume line or friendly thank-you.
literary
unflagging
when enthusiasm or attention stays at full strength
not when Unflagging fits constancy of spirit better than heavy practical labor.

tireless advocate
A tireless advocate kept the rural clinic on every funding agenda.
tireless efforts
Her tireless efforts connected hundreds of families with safe housing.
tireless work
The committee recognized twenty years of tireless work for clean water.

The definition and the example on this page are written here. The dictionaries above ground which meaning is being described, not the wording.