Ageis

2 clues
'-- just a number'
For ___ opportunity . . . " (Longfellow)
Similar answers:
Aagonizes
Aaverage
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Abag
Abagofnerves
Abeverage
Aboreis
Aboreisa
Aboutaguywhoisa
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Acage
Acamouflagesuit
Acceptedusage
Accompaniedstag
Accraghana
Acebandage
Acebandages
Acmeism