tender (adj.) Look up tender at Dictionary.com
"soft, easily injured," early 13c., from Old French tendre "soft, delicate; young" (11c.), from Latin tenerem (nominative tener) "soft, delicate; of tender age, youthful," from a derivative of PIE root *ten- "stretch" (see tenet), on the notion of "stretched," hence "thin," hence "weak" or "young." Compare Sanskrit tarunah "young, tender," Greek teren "tender, delicate," Armenian t'arm "young, fresh, green."

Meaning "kind, affectionate, loving" first recorded early 14c. Meaning "having the delicacy of youth, immature" is attested in English from early 14c. Related: Tenderly; tenderness. Tender-hearted first recorded 1530s.
tender (n.1) Look up tender at Dictionary.com
"person who tends another," late 15c., probably an agent noun formed from Middle English tenden "attend to" (see tend (v.2)); later extended to locomotive engineers (1825) and barmen (1883). The meaning "small boat used to attend larger ones" first recorded 1670s.
tender (v.) Look up tender at Dictionary.com
"to offer formally," 1540s, from Middle French tendre "to offer, hold forth" (11c.), from Latin tendere "to stretch, extend" (see tenet). The retention of the ending of the French infinitive is unusual (see render (v.) for another example).
tender (n.2) Look up tender at Dictionary.com
"formal offer for acceptance," 1540s, from tender (v.). Specific sense of "money offered as payment" is from 1740, in legal tender "currency which by law must be accepted from a debtor" (see legal).