Synonyms for Cap (same or very similar meaning)
WordNet sense 1 (a fruiting structure resembling an umbrella that forms the top of a stalked fleshy fungus such as a mushroom):
pileus
WordNet sense 2 (an upper limit on what is allowed):
ceiling
WordNet sense 3 (a mechanical or electrical explosive device or a small amount of explosive; can be used to initiate the reaction of a disrupting explosive):
detonator, detonating device
WordNet sense 4 (dental appliance consisting of an artificial crown for a tooth):
crownwork
WordNet sense 5 (the upper part of a column that supports the entablature):
capital, chapiter
WordNet sense 6 (lie at the top of):
crest
From the ODE community, based on WordNet
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