What does Head stand for?

Head's Tennessee Supreme Court Reports - 1858-59 - A publication (DLA)

Hand-Held Encryption and Authentication Device

Health Emergency and Dispensary, Inc. (SAUO)

Helium-Atom Diffraction (PDAA)

High Efficiency Amplifier embodying Dohertz principles (SAUS)

High Energy Astrophysics Division

Higher Education Affairs Directorate

High Explosive, Air Defence (SAUS)