Gerald Bostock ("born" circa 1964) is the fictional author of the poem used as the lyrics for the 1972 Jethro Tull album Thick as a Brick. The album cover is designed to look like a small village newspaper, the St. Cleve Chronicle & Linwell Advertiser. The front page story describes how eight-year-old Gerald, nicknamed "Little Milton", received an award for his poem, but the award was revoked after he used the word "g__r" during a television broadcast. The paper also presents "Bostock's" poem in its entirety and notes that Jethro Tull has decided to use the poem as the centerpiece of their new album (also reviewed in the paper).

Bostock was purely the invention of Ian Anderson and the band. Many fans have speculated as to what word "g__r" represents, with "goer" being the most-favored candidate.