dyed-in-the-wool Confirmed, inveterate; complete, thorough, unmitigated, out-and-out. When wool is dyed before being made into yarn, its color is more firmly fixed and lasting. A variant of this expression appeared in Sir Thomas North’s translation of Plutarch’s Lives of the Noble Grecians and Romans (1579):

hard-and-fast Ironclad, binding, strict, rigid, unbending. The literal, nautical sense of the term denotes a ship on shore or aground, stuck and immovable. It is probably this sense that gave rise to the figurative meaning in popular use today. Both the figurative and literal meanings date from the late 19th century.

man for all seasons A reliable, steadfast male; a man of principle who retains his integrity regardless of the situation. This expression alludes to a man who is unruffled by vicissitudes and who remains constant despite changing circumstances, like the weather. The phrase was popularized when Robert Bolt used it as the title of his dramatization of the life of Sir Thomas More (1960).

regular brick An agreeable, sincere male; a regular guy. This expression, referring to the solid, unvariegated constitution of a brick, describes a man who is genuinely amiable, unaffected, and reliable.

through thick and thin Through difficulties or adversity, in spite of any or all obstacles; faithfully, unwaveringly. According to the OED, thick and thin was originally thicket and thin wood. Thus this expression denoted an actual physical obstacle, as in the following quotation from Spenser’s Faerie Queene:

Currently through thick and thin is used figuratively as well, referring to any conceivable obstacle, and in context, connoting faithfulness.

true-blue Loyal, faithful; steadfast, staunch, unwavering, constant.

The color blue has long been the symbol of truth and constancy. Some conjecture the association arose because of the renowned fastness of Coventry blue dye. According to the OED, true-blue was applied to the Scottish Presbyterian or Whig party of the 17th century, the Covenanters having assumed blue as their partisan color in opposition to the royal red. Their doing so may have been connected with Numbers 15:38 of the Bible, in which the Lord commands Moses to have the Israelites put a blue ribbon on the fringes of the borders of their garments as a reminder to keep His commandments.