Synonyms for Specialise (same or very similar meaning)
WordNet sense 1 (devote oneself to a special area of work):
specialize
WordNet sense 2 (be specific about):
particularize, specify, particularise
WordNet sense 3 (become more special):
narrow, narrow down
WordNet sense 4 (evolve so as to lead to a new species or develop in a way most suited to the environment):
differentiate, speciate
From the ODE community, based on WordNet
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