δὲ [446 verses](conj) "But" is de which means "but," "yet," "however," and "on the other hand." It is the particle that joins sentences in an adversarial way but can also be an explanation of an indirect cause ("so") and a condition ("if"). In an  "if" (εἰ) clause or temporal "when" (ὅταν) clause the sense is "if/when... then." In a series begun by men, it means "on the other hand." In a listing, the sense is "then" or "yet." After an interruption, "so then." It can also be an explanation of cause ("so") and a condition ("if").  When used with a conditional starting a clause, the sense is "if/when...then." When used with a particle meaning "indeed" the sense is "on one hand...on the other hand." In a listing, the sense is "then" or "yet." After an interruption, "so then." -- The Greek word translated as "but" means "but," "yet," "however," and "on the other hand." It joins phrases in an adversarial way. Since it always falls in the second position, translating it as "however" often captures its feeling better.