Sentence:  During the day she'd lounge on the shore of the thermal lake in a fire-engine-red bikini, casting meaningful glances (with every <WSD>glanceful</WSD> worth its weight in gold) at the trade union miners, who were staying there gratis in the hopes of gaining  relief in the medicinal waters for whatever ailed them. 
Meaning of the word marked with <WSD> tags:  That which is communicated by a glance.