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couple, few, several

couple:            two and two only except in colloquial context.
                              (In reference to people usually takes plural verb.)

few:                    
an indefinite small number, the size of which varies with context;
                                        in a large flock of birds, a few might be several dozen

several
:            an indefinite small number—more than two, but less than many

See also few, fewer, less, lesser.