hide, shelter, shield
匿 centers on concealing something or someone from view: hiding, sheltering, or shielding from harm or discovery.
匿 combines 匚 (a container or enclosure) with 若, which likely contributes the sound and the idea of hiding or being concealed. The exact historical development is uncertain, but the structure suggests something placed inside a container to keep it hidden.
The outer 匚 is like a box or shelter, and inside is 若, which looks like a person crouching under grass. Imagine someone hiding in a box covered with grass to stay concealed.
For トク, imagine hiding a special talking duck inside the box: duck -> トク, and the duck is safely hidden away.
anonymity; using an assumed name
hiding; concealment
to shelter (e.g. a fugitive); to harbour; to harbor; to hide; to give refuge to
concealment (esp. of wrongdoings or criminals); sheltering; harboring
shelter; shield; hide
anonymous FTP
anonymization (of data); anonymisation
request to remain anonymous; name withheld by request
anonymity
anonymous criticism
anonymous textboard
anonymous partnership; silent partnership; anonymous association
anonymous shipping
ad hoc group formed to commit crimes
to shelter a criminal
(crime of) harboring a fugitive (harbouring)
secret name; code name
confidentiality; secrecy
privilege (e.g. "attorney-client privilege")
diving under cover and hiding