The name means he who is victorious over death. He is a form of Shiva and this prayer which occurs in Rudram is supposed to give us long life as well as helps us to get rid of fear over death.
Om Tryambakam yajamahe
Sugandhim pushtivardhanam
Urvarurkamiva bhandhanam
Mrityor mukshiya ma -mrtat.
We salute and respect,
Him, who is naturally scented,
Him who looks after his devotees with mercy,
And him who has three eyes.
And pray and request,
To move us away from the catch of death,
Like the cucumber separated from its stalk,
And firmly put us in the path of salvation.
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Translated By P.R.Ramachander
Om Tryambakam yajamahe
Sugandhim pushtivardhanam
Urvarurkamiva bhandhanam
Mrityor mukshiya ma -mrtat.
We salute and respect,
Him, who is naturally scented,
Him who looks after his devotees with mercy,
And him who has three eyes.
And pray and request,
To move us away from the catch of death,
Like the cucumber separated from its stalk,
And firmly put us in the path of salvation.
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Translated By P.R.Ramachander