Sentence:  Research and development activities undertaken by the Secretary shall be coordinated or conducted jointly with the Department of Defense to the end that developments under this Act which are primarily of a civil nature will contribute to the defense of the Nation and that developments which are primarily of a <WSD>military</WSD> nature will , to the greatest practicable extent compatible with military and security requirements , be available to advance the purposes of this Act and to strengthen the civil economy of the Nation . 
Meaning of the word marked with <WSD> tags:  associated with or performed by members of the armed services as contrasted with civilians