ally [ME] Latin alligere ‘combine together’, formed from ad- ‘to(gether)’ and ligare ‘bind’ developed into two closely related words in Old French: alier which became ally in English, and aloyer which became alloy [L16th], but found earlier in the now obsolete allay [ME]. Ligare is also hidden in furl [L16th] which comes from French ferler, from ferm ‘firm’ and lier ‘bind’; league [LME] a binding together; and oblige [ME] originally meaning ‘bind by oath’.