Synonyms for Sr (same or very similar meaning)
WordNet sense 1 (a soft silver-white or yellowish metallic element of the alkali metal group; turns yellow in air; occurs in celestite and strontianite):
strontium
WordNet sense 2 (the unit of solid angle adopted under the Systeme International d'Unites):
steradian
From the ODE community, based on WordNet
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