Synonyms for developments vital to national security. b. secret
de·vel·op·ments vi·tal to na·tion·al se·cu·ri·ty. b. se·cret

The ASL fingerspelling provided here is most commonly used for proper names of people and places; it is also used in some languages for concepts for which no sign is available at that moment.

There are obviously specific signs for many words available in sign language that are more appropriate for daily usage.