More glossary terms and definitions, A-C:
ABWEHR-German military secret police.

BAKER STREET- SOE headquarters in London from October 1940...

BCRA- Bureau Central de Renseignments et d' Action.

BLIND DROP- Agents parachuting into France without a reception committee to meet them.

CACHETTE- An agent's hiding place.

CIRCUIT- SOE's F Section was organized in circuits named after trades and occupations, e.g. Footman, Fireman, Salesman, Scientist, Stationer.

COMBAT- French Resistance group in unoccupied zone (a.k.a. Zone Libre) working with RF Section not F Section.

COUP DUR- Heavy roundup of suspects including house searches intended to flush out resisters and partisans. In Italy this is called "rastrallimenti".

Above information from Binney's book listed in my bib.