Re: table called 'configuration' cannot be dropped

I am running Postgresql version 9.5.14 on Ubuntu linux 16.04.

My schema defines a table called configuration.

From psql:

# \d configuration

            Table "public.configuration"

     Column     |          Type          | Modifiers 

----------------+------------------------+-----------

 parametername  | character varying(64)  | not null

 parametervalue | character varying(256) | 

Indexes:

    "configuration_pkey" PRIMARY KEY, btree (parametername)

PROBLEM:

When in psql, I  type:

# DROP TABLE configuration;

psql just hangs.  No further output from psql.  

If I hit CTRL-C, it responds as expected with:

^CCancel request sent

ERROR:  canceling statement due to user request

But why is psql stuck on the DROP statement?

Is configuration a reserved word or pre-defined table? 

Do I need to rename the table?

Thanks,

Dan McCue