trouble of going somewhere; inconvenience of making a trip
Used when acknowledging the effort someone has made to come, often in polite expressions like 足労をかける or 足労をねぎらう. Not a casual word; it carries a formal, appreciative tone.
Thank you for coming all this way; I'm sorry for the trouble of your journey.
The company president visited the site specifically to thank everyone for their trouble in coming.
trouble of coming; kind visit
Compound of 足 (foot, leg) and 労 (labor, toil). The exact historical derivation is uncertain, but the combination naturally conveys the idea of 'foot-trouble' or the effort of traveling.