一縷[ichiru] a thread
縷説[rusetsu] detailed explanation
縷々[ruru] continuously
縷縷綿綿[rurumenmen] going on and on in tedious detail

一縷の望み[ichirunonozomi] gleam (ray) of hope
繁縷[hakobe] chickweed
繁縷塩[hakobejio] chickweed (stitchwort) roasted and mixed with salt, then ground into a powder for use as toothpaste