Meanings

coming into and out of sight

hidden command

secret

retreat

Easter egg

hidden line removal

hidden attribute

hidden-line elimination

hidden file

hidden line and surface removal

hidden line and surface removal

hidden line (in a technical drawing)

hidden Markov model

hidden surface removal

cover-up

fascia board

hiding at all costs

invisibility (through magic)

helping a criminal to avoid arrest

clandestine Christian (during the Edo period)