Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
allĭgātor (adl-), ōris, m. [alligo], one who binds to (only in Col.): adligatoris cura, Col. 4, 13, 1; so id. 4, 17, 5; 4, 20, 1; 4, 26, 4.