39 female found grape size lump in groin. painless, hard, not movable. feels like attached to tendon or something. noticed about 10 days ago.

Time to see MD: The lump could be due to any number of benign reasons or a lymph node enlargement. However, a MD has to see the area to make that determination. See one soon.

Possibilities: This is a common location for lymph glands that act as strainers for body serum. They will often swell in response to irritation/infection/bug bites on the leg on that side or the tissue near the genitals. They enlarge when working hard & may go back down if conditions improve. The only way to confirm or exclude something requiring specific treatments is an office evaluation.